tree 3a9367c391418c1375a6c86f678b3f047cacc03f
parent ef38670cae8462d579da983c1863f96717cccee6
author Mathieu Chartier <mathieuc@google.com> 1402424551 -0700
committer Mathieu Chartier <mathieuc@google.com> 1403207825 -0700

Add mark compact collector.

The mark compact collector is a 4 phase collection, doing a normal
full mark_sweep, calculating forwarding addresses of objects in the
from space, updating references of objects in the from space, and
moving the objects in the from space.

Support is diabled by default since it needs to have non movable
classes and field arrays. Performance numbers is around 50% as fast.

The main advantage that this has over semispace is that the worst
case memory usage is 50% since we only need one space isntead of two.

TODO: Make field arrays and classes movable. This causes complication
since Object::VisitReferences relies on these, so if we update the
fields of an object but another future object uses this object to
figure out what fields are reference fields it doesn't work.

Bug: 14059466

Change-Id: I661ed3b71ad4dde124ef80312c95696b4a5665a1