Implement card table verification.
Card table verification occurs just before scanning the card table
during a concurrent GC. Each object in the bitmap is visited and the
number of white (unmarked) references are counted. If an object has
unmarked objects it is by definition gray and must reside on a dirty
card. If the object is not on a dirty card, the verification routine
aborts the VM.
Because the processing of weak roots and references has yet to occur,
reachable reference objects with unmarked referents and weak interned
strings may still be gray. These objects are checked during the card
table scan and ignored if their card is not dirty.
Change-Id: I64d145aa4719fb52eb9e3bb91efaf4dcfacd6e0c
5 files changed