Ensure CopyElementsImpl is always executed so it fills in holes even if from_size is 0. Allow Fixed…

Ensure CopyElementsImpl is always executed so it fills in holes even if from_size is 0. Allow FixedDoubleArray::cast to also support FixedArray with size 0.

Committed: https://code.google.com/p/v8/source/detail?r=13000

[Toon Verwaest, 2012-11-19 10:16:05]

PTAL

[danno, 2012-11-19 12:45:53]

lgtm

[Michael Starzinger (Google), 2012-11-19 12:55:46]

Drive-by-comments.

https://chromiumcodereview.appspot.com/11280054/diff/1/src/objects-inl.h
File src/objects-inl.h (right):

https://chromiumcodereview.appspot.com/11280054/diff/1/src/objects-inl.h#newc...
src/objects-inl.h:2345: FixedDoubleArray* FixedDoubleArray::cast(Object* object)
{
As discussed offline, I don't like this new casting function. It is lying about
the return type. Can we instead have a second
FixedDoubleArray::castButAllowEmptyFixedArray() that does this? That one would
still be lying about the return type, but at least the function name is scary
enough to let people know what's going on.

BTW, I am flexible about the name as long as it sounds complicated and scary. :)

[Toon Verwaest, 2012-11-19 14:45:00]

addressed comments.