cycleBufferAisOpen = !cycleBufferAisOpen;
  private final void processCycleBufs() {    VM_Address obj;    AddressQueue src = (cycleBufferAisOpen) ? cycleBufferA : cycleBufferB;    AddressQueue tgt = (cycleBufferAisOpen) ? cycleBufferB : cycleBufferA;    while (!(obj = src.pop()).isZero()) {      if (SimpleRCHeader.isLiveRC(VM_Magic.addressAsObject(obj))) {	if (SimpleRCHeader.isPurple(VM_Magic.addressAsObject(obj)))	  tgt.push(obj);	else	  SimpleRCHeader.clearBufferedBit(VM_Magic.addressAsObject(obj));      } else	freeBuffer.push(obj);    }  }