/**
* Return the lock index for a given lock word. Assert valid index ranges, that the fat lock bit
* is set, and that the lock entry exists.
*
* @param lockWord The lock word whose lock index is being established
* @return the lock index corresponding to the lock workd.
*/
@Inline
@Uninterruptible
public static int getLockIndex(Word lockWord) {
int index = lockWord.and(TL_LOCK_ID_MASK).rshl(TL_LOCK_ID_SHIFT).toInt();
if (VM.VerifyAssertions) {
if (!(index > 0 && index < Lock.numLocks())) {
VM.sysWrite("Lock index out of range! Word: ");
VM.sysWrite(lockWord);
VM.sysWrite(" index: ");
VM.sysWrite(index);
VM.sysWrite(" locks: ");
VM.sysWrite(Lock.numLocks());
VM.sysWriteln();
}
VM._assert(index > 0 && index < Lock.numLocks()); // index is in range
VM._assert(lockWord.and(TL_STAT_MASK).EQ(TL_STAT_FAT)); // fat lock bit is set
}
return index;
}
