in preparation of the introduction of ES6 'symbols' (aka private/unique names).
The SymbolTable became the StringTable. I also made sure to adapt all comments. The only remaining use of the term "symbol" (other than unrelated uses in the parser and such) is now 'NewSymbol' in the API and the 'V8.KeyedLoadGenericSymbol' counter, changing which might break embedders.
The one functional change in this CL is that I removed the former 'empty_string' constant, since it is redundant given the 'empty_symbol' constant that we also had (and both were used inconsistently).
R=yangguo@chromium.org
BUG=
Review URL: https://codereview.chromium.org/12210083
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13781 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
As a special case, for checks on index expressions with the form (expr + constant) if a smaller constant is checked later in the DT also eliminate the check.
Finally, if a larger constant is checked later in the same BB do the more general check (larger constant) earlier instead of the less general one.
This will not cause useless deoptimizations because, since we are in the same BB, all the checks would have been executed anyway.
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/10032029
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11437 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Better support for 'polymorphic' JS and external arrays
Allow keyed store/load stubs to switch between external array and fast JS arrays without forcing a state transition to the generic stub.
There CL consists of two pieces of functionality. First, code stubs for fast element arrays don't immediately transition to the MEGAMORPHIC state when there's a map mismatch. Second, two ICs are cached per map for fast elements, the MONOMORPHIC version, and a new MEGAMORPHIC version that handles two or more different maps and dispatches to shared stubs to perform the array operation.
Review URL: http://codereview.chromium.org/7036016
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7935 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Allow keyed store/load stubs to switch between external array and fast JS arrays without forcing a state transition to the generic stub.
There CL consists of two pieces of functionality. First, code stubs for fast element arrays don't immediately transition to the MEGAMORPHIC state when there's a map mismatch. Second, two ICs are cached per map for fast elements, the MONOMORPHIC version, and a new MEGAMORPHIC version that handles two or more different maps. Currently, the only array types supported by the MEGAMORPHIC stub are fast elements for objects and JSArrays.
BUG=
TEST=
Review URL: http://codereview.chromium.org/6894003
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7917 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Worth mentioning:
- Specialized versions of pixel array and store/loads inside the generic stubs have been removed, since to have parity for all external arrays, 8 different versions would have to be inlined/checked.
- There's a new constant in v8.h for external arrays with pixel array elements.
Review URL: http://codereview.chromium.org/6546036
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7106 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
If the instance of is performed against what is beliwed to be a constant global function inline the instance of check and have the call to the instanceof stub in deferred code. The inlined check will be patched by the instanceof stub when called from deferred code. This is indicated by the lithium instruction LInstanceOfKnownGlobal.
To help the patching the delta from the return address to the patch site is placed just below the return address in the edi slot of the pushad/popad ares. This is safe because the edi register (which is pushed last) is a temporary for the lithium instruction.
As the instanceof stub can call other JavaScript an additional marking for saving all double registers have been added.
Also tweaked the instanceof stub to produce true/false objects instead of 0/1 for the case with deferred code.
Review URL: http://codereview.chromium.org/5990005
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6173 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Change more functions used by the Compiler class to have a uniform
interface: they get passed as argument an input/output pointer to a
CompilationInfo that they mutate if they succeed, and they return a
flag telling whether they succeeded.
Also, remove some unnecessary timers.
Review URL: http://codereview.chromium.org/3561012
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5583 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Contextual load requires only a map check followed by a cell hole
check so we can generate pretty compact code for that. The fact that
we have inlined code is marked by mov ecx, offset instruction after
the IC call. Inlining is only enabled inside loops and in non-builtin
functions.
The generated code size increase is about 3%. This descreased the
pc-to-code cache hit rate in some of the benchmarks that trigger
GC. To compensate we now have 4 times as much entries in the cache.
Review URL: http://codereview.chromium.org/3402014
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5497 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
the code object's instructions.
This allows us to find a code object using just the pc. This approach
uses a cache (PcToCodeCache) to make sure we don't continuously have
to iterate heap pages.
This change eliminates the need for cooking and uncooking of stack frames.
Review URL: http://codereview.chromium.org/3226014
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5369 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
