Enable map dependency to in-flight compilation info.

Enable map dependency to in-flight compilation info.

R=ulan@chromium.org
BUG=

Committed: https://code.google.com/p/v8/source/detail?r=15005

[Yang, 2013-06-07 11:06:58]

On 2013/06/06 11:49:44, Yang wrote:

I've uploaded a second patch set to remove the changes to transition maps and
initial object/array maps to put into a second CL.

[ulan, 2013-06-07 13:21:29]

LGTM

https://codereview.chromium.org/16542003/diff/6001/src/compiler.cc
File src/compiler.cc (right):

https://codereview.chromium.org/16542003/diff/6001/src/compiler.cc#newcode146
src/compiler.cc:146: for (int j = 0; j < group_maps->length(); j++) {
This has O(n^2) complexity. It is probably OK. I am not sure if there are cases
with large number of maps in code.

https://codereview.chromium.org/16542003/diff/6001/src/objects.cc
File src/objects.cc (right):

https://codereview.chromium.org/16542003/diff/6001/src/objects.cc#newcode11098
src/objects.cc:11098: info->dependent_maps(group)->Add(Handle<Map>(this),
info->zone());
Note that this can add duplicate maps into dependent_maps(group). If performance
becomes an issue, we might want to revisit this.

[Yang, 2013-06-07 13:27:19]

Committed patchset #3 manually as r15005 (presubmit successful).