Moving the WhitenessWitness back to DescriptorArray.

Moving the WhitenessWitness back to DescriptorArray.

TransitionArrays never allocate while being created.

Committed: https://code.google.com/p/v8/source/detail?r=12519

[Toon Verwaest, 2012-09-13 09:34:34]

PTAL.

[Michael Starzinger, 2012-09-14 11:18:08]

https://chromiumcodereview.appspot.com/10908237/diff/1/src/transitions-inl.h
File src/transitions-inl.h (right):

https://chromiumcodereview.appspot.com/10908237/diff/1/src/transitions-inl.h#...
src/transitions-inl.h:203: void TransitionArray::Set(int transition_number,
String* key, Map* target) {
Now that this method no longer takes a WhitenessWitness we need to rename this
method to NoIncrementalWriteBarrierSet() so that it is clear that we can only
call this on white objects. Otherwise this will become a bucket of bugs.

[Toon Verwaest, 2012-09-14 12:28:04]

Addressed comments, PTAL.

https://chromiumcodereview.appspot.com/10908237/diff/1/src/transitions-inl.h
File src/transitions-inl.h (right):

https://chromiumcodereview.appspot.com/10908237/diff/1/src/transitions-inl.h#...
src/transitions-inl.h:203: void TransitionArray::Set(int transition_number,
String* key, Map* target) {
On 2012/09/14 11:18:08, Michael Starzinger wrote:
> Now that this method no longer takes a WhitenessWitness we need to rename this
> method to NoIncrementalWriteBarrierSet() so that it is clear that we can only
> call this on white objects. Otherwise this will become a bucket of bugs.

Done.

[Michael Starzinger, 2012-09-14 15:04:50]

LGTM (with one comment).

https://chromiumcodereview.appspot.com/10908237/diff/4002/src/transitions.cc
File src/transitions.cc (right):

https://chromiumcodereview.appspot.com/10908237/diff/4002/src/transitions.cc#...
src/transitions.cc:85: result->Set(0, name, target);
Shouldn't that be NoIncrementalWriteBarrierSet as well?