import static com.google.common.hash.LittleEndianByteArray.load64Safely;
import static java.lang.Long.rotateRight;

import com.google.common.annotations.VisibleForTesting;

/**
 * Implementation of Geoff Pike's fingerprint2011 hash function. See {@link Hashing#fingerprint2011}
 * for information on the behaviour of the algorithm.
 *
 * <p>On Intel Core2 2.66, on 1000 bytes, fingerprint2011 takes 0.9 microseconds compared to

 *
 * <ul>
 *   <li>comparisons (signed values can be negative)
 *   <li>division (avoided here)
 *   <li>shifting (right shift must be unsigned)
 * </ul>
 *
 * @author Kyle Maddison
 * @author Geoff Pike
 */
@ElementTypesAreNonnullByDefault
final class FarmHashFingerprint64 extends AbstractNonStreamingHashFunction {
  static final HashFunction FARMHASH_FINGERPRINT_64 = new FarmHashFingerprint64();