Track up to 5 stable maps as field type.

Track up to 5 stable maps as field type.

R=svenpanne@chromium.org

Committed: https://code.google.com/p/v8/source/detail?r=20831

[Benedikt Meurer, 2014-04-17 06:23:33]

PTAL

[Sven Panne, 2014-04-17 06:43:40]

LGTM with nits.

https://codereview.chromium.org/240813002/diff/1/src/objects.cc
File src/objects.cc (right):

https://codereview.chromium.org/240813002/diff/1/src/objects.cc#newcode2539
src/objects.cc:2539: num_old_classes + num_new_classes <= 5 &&
Perhaps give the "5" a name...

https://codereview.chromium.org/240813002/diff/1/src/objects.cc#newcode2541
src/objects.cc:2541: return HeapType::Union(new_field_type, old_field_type,
isolate);
As discussed offline: Perhaps calculate the union first and then check its size.

[Benedikt Meurer, 2014-04-17 07:26:34]

https://codereview.chromium.org/240813002/diff/1/src/objects.cc
File src/objects.cc (right):

https://codereview.chromium.org/240813002/diff/1/src/objects.cc#newcode2539
src/objects.cc:2539: num_old_classes + num_new_classes <= 5 &&
On 2014/04/17 06:43:41, Sven Panne wrote:
> Perhaps give the "5" a name...

Done.

https://codereview.chromium.org/240813002/diff/1/src/objects.cc#newcode2541
src/objects.cc:2541: return HeapType::Union(new_field_type, old_field_type,
isolate);
On 2014/04/17 06:43:41, Sven Panne wrote:
> As discussed offline: Perhaps calculate the union first and then check its
size.

Done.

[Benedikt Meurer, 2014-04-17 08:22:33]

Committed patchset #2 manually as r20831 (presubmit successful).

[ulan, 2015-02-10 10:48:07]

On 2014/04/17 08:22:33, Benedikt Meurer wrote:
> Committed patchset #2 manually as r20831 (presubmit successful).

This change introduced memory leak:
https://code.google.com/p/v8/issues/detail?id=3877