int oldValue, markBit;
VM_Word oldValue, markBit;
  public static boolean testAndMark(VM_Address ref, int value)    throws VM_PragmaUninterruptible, VM_PragmaInline {    int oldValue, markBit;    do {      oldValue = VM_Interface.prepareAvailableBits(ref);      markBit = oldValue & MARK_BIT_MASK;      if (markBit == value) return false;    } while (!VM_Interface.attemptAvailableBits(ref,oldValue,oldValue ^ MARK_BIT_MASK));    return true;  }