if (VM.VerifyAssertions) VM.assert(index >= 0 && index < BITS_PER_INT);
if (VM.VerifyAssertions) VM._assert(index >= 0 && index < BITS_PER_INT);
  private int bitIndex (Object object, int wordIndex) throws VM_PragmaUninterruptible {    int index = ((VM_Magic.objectAsAddress(object).diff(baseAddress)) / ALIGNMENT) % BITS_PER_INT;    if (DEBUG) {      VM.sysWrite(" {Length ", marks.length);      VM.sysWrite(" base ", baseAddress);      VM.sysWrite(" high ", highAddress);      VM.sysWrite(";   Object ", VM_Magic.objectAsAddress(object));      VM.sysWrite(" word ", wordIndex);      VM.sysWrite(" bit ", index, "} ");    }    if (VM.VerifyAssertions) VM.assert(index >= 0 && index < BITS_PER_INT);    return index;  }