Object model changes
----------------------------------------
New fixed_cow_array_map is used for the elements array of a JSObject
to mark it as COW. The JSObject's map and other fields are not
affected. The JSObject's map still has the "fast elements" bit set. It
means we can do only the receiver map check in keyed loads and the
receiver and the elements map checks in keyed stores. So introducing
COW arrays doesn't hurt performance of these operations. But note that
the elements map check is necessary in all mutating operations because
the "has fast elements" bit now means "has fast elements for reading".
EnsureWritableFastElements can be used in runtime functions to perform
the necessary lazy copying.
Generated code changes
----------------------------------------
Generic keyed load is updated to only do the receiver map check (this
could have been done earlier). FastCloneShallowArrayStub now has two
modes: clone elements and use COW elements. AssertFastElements macro
is added to check the elements when necessary. The custom call IC
generators for Array.prototype.{push,pop} are updated to avoid going
to the slow case (and patching the IC) when calling the builtin should
work.
COW enablement
----------------------------------------
Currently we only put shallow and simple literal arrays in the COW
mode. This is done by the parser.
Review URL: http://codereview.chromium.org/3144002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5275 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Upgraded the CodeGenerator::ToBoolean() function in the ARM backend to use complete JIT code generation and not make runtime calls to ToBool (when VFP is enabled).
This change also includes the vcmp VFP instruction that supports a constant 0.0 as the second operand.
Patch by Subrato K De <subratokde@codeaurora.org>
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5267 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This should help in cases like:
function Constructor() {
this.foo = constFunction;
this.bar = "baz";
}
for (...) {
o = new Constructor();
// Constant call IC will work.
o.foo();
// Inlined property load will see the same map.
use(o.bar);
}
This change also fixes a latent bug in custom call IC-s for strings
exposed by string-charcodeat.js.
Review URL: http://codereview.chromium.org/3160006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5254 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This adds a check to the fast case string add to ensure that the String object still have the default valueOf function. The default valueOf is sitting on a hidden prototype of String.prototype.
Before using the fast case valueOf the object is checked for a local valueOf property. For slow case objects this check always reports true (the dictionary is not probed, so valueOf might be there) and for fast case objects the descriptor array is checked for the valueOf symbol (just liniar scan). After that the prototype is checked for beeing the initial value of String.prototype. If this all pass (that is the default valueOf is still in place) this result is cached on the map making the check fast the next time.
This is only implemented in the optimizing compiler, as the two usages of %_IsStringWrapperSafeForDefaultValueOf is never hit by the full compiler.
I will port to x64 and ARM when this has been reviewed for ia32.
I will remove the performance counters prior to final commit.
BUG=http://code.google.com/p/v8/issues/detail?id=760
TEST=test/mjsunit/regress/regress-760-1.js
TEST=test/mjsunit/regress/regress-760-2.js
Review URL: http://codereview.chromium.org/3117006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5252 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
in allowing more flexible compilation and to simplify builtins lookup.
This changes a number of places where code objects are assigned to
SharedFunctionInfo objects to also assign this code object to the
JSFunction. In addition, the code flushing is changed slightly to
accomodate this (we need to flush the code from functions pointing to
SharedFunctionInfo objects that has already been flushed).
Review URL: http://codereview.chromium.org/3120006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5233 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
and the value can share a register. We need to remove this aliasing
before modifying the registers.
I haven't managed to generate a stand-alon test case for this
yet. I'll do that as a separate change. This was found while loading
Wave.
Review URL: http://codereview.chromium.org/3039025
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5127 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This includes adding a new inline IsSpecObject method to the code
generator. The old approach was somehow ineffecient since we would
call both IsObject, IsUndetectable and IsFunction to determine if
something was an object according to the spec. This change introduces
a new macro that determines if something is an object according to the
spec (and this does not include null).
This change also corrects a few places where undetectable objects was
not allowed even when they should be (priorly they would use only
IS_SPEC_OBJECT_OR_NULL, which would return false on an undetectable
object, the new IS_SPEC_OBJECT returns true on an undetectable object.
Review URL: http://codereview.chromium.org/2877018
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5087 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
