The different length string types was used to encode the string length and the hash in one field. This is now split into two fields one for length and one for hash. The hash field still encodes the array index of the string if it has one. If an array index is encoded in the hash field the string length is added to the top bits of the hash field to avoid a hash value of zero.
On 32-bit this causes an additional 4 bytes to be used for all string objects. On 64-bit this will be half on average dur to pointer alignment.
Review URL: http://codereview.chromium.org/436001
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3350 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Summary:
This change fixes a performance regression introduced by the special
handling of regular expressions in typeof expressions.
As a result we regain ~8% speedup on 3d-raytrace and ~13% on boyer
(vs bleeding edge)
Description:
The macros IS_OBJECT and IS_FUNCTION are frequently used in the
JS runtime functions.
By introducing new inlined runtime functions %_IsFunction and %_IsObject
we avoid invoking the more expensive %_ClassOf function plus comparing
its result to a string.
Review URL: http://codereview.chromium.org/399111
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3335 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Condition block of do/while statements is a valid break location so it should have its own position. The block is represented by a regular Expression node so we cannot store the position in it, instead the position is stored in a separate field in DoWhileStatement AST node.
BUG=514
Review URL: http://codereview.chromium.org/385136
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3312 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
available. We use this to ensure that snapshots on MacOSX can
use SSE2 instructions. Also clean up and assertify the
handling of things we can't do when we are generating a
snapshot. Fix a bug in the new serialization tests where
they activated Snapshot::enable() too late after code had been
generated that assumed no snapshots.
Review URL: http://codereview.chromium.org/391051
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3301 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
regular expressions to be consistent with typeof in other contexts.
Typeof regular expressions should now be 'function' in all contexts.
In the JS natives, IS_FUNCTION, IS_OBJECT, and IS_REGEXP return the
same answers as before.
Review URL: http://codereview.chromium.org/360053
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3231 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
In the generated code for function.apply there was a loop checking the stack limit for interruption. This loop would call into the runtime system to handle interuption and keep running until there was no interruption. However if the interuption was debug break the runtime system would never clear the interruption as debug break is prevented in builtins are prevented and the assumption here was that returning with the debug break flag set would move execution forward.
Renamed initial_jslimit and initial_climit to real_jslimit and real_climit. Renamed a few external references related to the stack limit as well.
Exposed the real stack limit to generated code to make the stack check when entering function.apply use the real stack limit and not the stack limit which is changed to signal interruption.
Added the real stack limit to the roots array.
BUG=http://code.google.com/p/v8/issues/detail?id=493
TEST=cctest/test-debug/DebugBreakFunctionApply
Review URL: http://codereview.chromium.org/345048
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3229 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
separate JS stack.
In exception handling, we need to be able to compare addresses into
the JavaScript portion of the stack with the address of a C++ handler
on the stack. Since the stacks are separate on the simulator, we need
a JavaScript stack address corresponding to a C++ try catch handler in
order to perform valid address comparisons.
On the simulator, we now link the C++ try catch handlers indirectly
through the JS stack and use the JS stack indirection address for
comparisons.
JS C++
handler
[C++ address] <------ next_
\
\
\----> handler
[C++ address] <------ next_
On actual hardware the C++ try catch handlers continue to be directly
linked.
BUG=http://code.google.com/p/v8/issues/detail?id=271
Review URL: http://codereview.chromium.org/360004
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3228 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
There were two separate implementations of the function
'BuildBoilerplate' that is used to compile function declarations and
function literals. The implementations did not do exactly the same
thing. In particular, one ignored the flag --lazy.
Combine the two implementations.
Review URL: http://codereview.chromium.org/360011
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3218 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
used to signal that an expression was the immediate subexpression of
typeof, or (?) in the arm of a conditional expression itself in the
typeof state.
It was inconsistently consulted. It was not used for property loads,
but only for slot loads. This means that we matched the Webkit JSC
(not Spidermonkey) behavior for:
typeof(true ? x : y) // throws ReferenceError
and we matched the SpiderMonkey behavior (not JSC) for:
with ({}) { typeof(true ? x : y) } // ==> "undefined"
Now we are expected to match the JSC behavior in all cases.
Review URL: http://codereview.chromium.org/362004
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3212 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
directly-applied function literals that are themselves compiled with
the top-level code generator.
The choice is guarded by a test that the function is anonymous (thus
not expected to be recursive) and not in a loop.
A compilation hint is set in the shared function info and used to make
the choice.
Review URL: http://codereview.chromium.org/341081
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3206 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
context. Test contexts are used for the left subexpressions of
short-circuited boolean operators. The right subexpressions inherit
their expression context from the binary op expression.
Compilation of short-circuited operations in effect and test context
is straightforward:
effect(e0 || e1) =
test(e0, L0, L1)
L1: effect(e1)
L0:
test(e0 || e1, L0, L1) =
test(e0, L0, L2)
L2: test(e1, L0, L1)
Because the value of the first subexpression may be needed as the
value of the whole expression in a value context, we introduce a
hybrid value/test contest (the value is needed if true, but not if
false).
value(e0 || e1) =
value/test(e0, L0, L1)
L1: value(e1)
L0:
The compilation of value/test and test/value (introduced by boolean
AND) is:
value/test(e0 || e1, L0, L1) =
value/test(e0, L0, L2)
L2: value/test(e1, L0, L1)
test/value(e0 || e1, L0, L1) =
test(e0, L0, L2)
L2: test/value(e1, L0, L1)
Boolean AND is the dual. The AST nodes themselves (not their parents)
are responsible for producing the proper result (effect, value, or
control flow) depending on their context.
Review URL: http://codereview.chromium.org/339082
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3187 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
o.x() and o[expr]()
other changes:
- Fix missing relocation info for StoreIC on global object.
- Generate only one common return sequence instead of always appending
"return <undefined>" at the end of each function: The first JS
return-statement will generate the common return sequence. All
other return-statements will generate a unconditional branch to the common
return sequence.
Review URL: http://codereview.chromium.org/340037
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3183 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The code for .result = (b.y = 99) where b is a global variable is:
push [esi+0x17]
mov ecx,0xf5c229ad ;; object: 0xf5c229ad <String[1]: b>
call LoadIC_Initialize
nop
mov [esp],eax
mov eax,0xc6
mov ecx,0xf5c25c41 ;; object: 0xf5c25c41 <String[1]: y>
call StoreIC_Initialize
nop
mov [esp],eax
pop [ebp+0xf4]
There is still some room for improvement in the generated code.
Other changes:
- Replaced switch-statement in FastCodeGenerator::VisitProperty with DropAndMove(...)
- Do not emit nop after IC calls on ARM.
Review URL: http://codereview.chromium.org/347001
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3180 ce2b1a6d-e550-0410-aec6-3dcde31c8c00