Implement neededBlocks

Signed-off-by: Edward Z. Yang <ezyang@mit.edu>
Resource Limits

Signed-off-by: Edward Z. Yang <ezyang@mit.edu>
Store old RC in update frame.

Signed-off-by: Edward Z. Yang <ezyang@mit.edu>
Add preliminary primop support for RC.

Signed-off-by: Edward Z. Yang <ezyang@mit.edu>
Added forceAllocGroupFor, forceAllocBlockFor, (force)allocateLargeFor, allocate0, cmmMaybeAllocate, heap-overflow handling

Signed-off-by: Edward Z. Yang <ezyang@mit.edu>
Wire up prim-ops to use cmmMaybeAllocate

Signed-off-by: Edward Z. Yang <ezyang@mit.edu>
Approved API for static closure blocks

Signed-off-by: Edward Z. Yang <ezyang@mit.edu>
Uncharge blocks properly on freeGroup

Signed-off-by: Edward Z. Yang <ezyang@mit.edu>
Properly allocate todo block from appropriate RC

Signed-off-by: Edward Z. Yang <ezyang@mit.edu>
Improved sanity checking for RC invariants.

Signed-off-by: Edward Z. Yang <ezyang@mit.edu>