if (VM.VerifyAssertions) VM._assert(!SimpleRCHeader.isGreen(obj)); SimpleRCHeader.clearBufferedBit(obj);
if (VM.VerifyAssertions) VM._assert(!SimpleRCBaseHeader.isGreen(obj)); SimpleRCBaseHeader.clearBufferedBit(obj);
  private final void doCollectPhase() {    VM_Address obj;    AddressQueue src = (cycleBufferAisOpen) ? cycleBufferA : cycleBufferB;    rcCollector.collectPhase();    while (!(obj = src.pop()).isZero()) {      if (VM.VerifyAssertions) VM._assert(!SimpleRCHeader.isGreen(obj));      SimpleRCHeader.clearBufferedBit(obj);      rcCollector.collectWhite(obj, this);    }    processFreeBufs();  }