Fix unsafe use of DescriptorWriter across allocation....

Fix unsafe use of DescriptorWriter across allocation.

DescriptorWriters hold a raw pointer to the descriptor array and they
are therefore not GC safe.

Committed: http://code.google.com/p/v8/source/detail?r=2384

[iposva, 2009-07-08 02:12:21]

LGTM with comments.

-Ivan

http://codereview.chromium.org/149304/diff/1/2
File src/factory.cc (right):

http://codereview.chromium.org/149304/diff/1/2#newcode573
Line 573: DescriptorWriter w(*result);
Please put a scope around this with a comment that a DescriptorWriter can be
safely used here because copying entries does not cause a GC.

http://codereview.chromium.org/149304/diff/1/2#newcode597
Line 597: // Do not use the DescriptorWriter 'w' here. SymbolFromString
At which point you can skip the reference to w in this comment and instead just
say that SymbolFromString can cause allocation which is why we need to use
handle based accesses to the result array.

[Mads Ager (chromium), 2009-07-08 03:20:44]

I'll put this change back now to get rid of the unsafe use of the
DescriptorWriter.  As we discussed offline, I'll experiment with removing the
DescriptorStreams entirely.

http://codereview.chromium.org/149304/diff/1/2
File src/factory.cc (right):

http://codereview.chromium.org/149304/diff/1/2#newcode573
Line 573: DescriptorWriter w(*result);
On 2009/07/08 02:12:21, iposva wrote:
> Please put a scope around this with a comment that a DescriptorWriter can be
> safely used here because copying entries does not cause a GC.

Done.

http://codereview.chromium.org/149304/diff/1/2#newcode597
Line 597: // Do not use the DescriptorWriter 'w' here. SymbolFromString
On 2009/07/08 02:12:21, iposva wrote:
> At which point you can skip the reference to w in this comment and instead
just
> say that SymbolFromString can cause allocation which is why we need to use
> handle based accesses to the result array.

Done.