presto-spi/src/main/java/io/prestosql/spi/type/TinyintType.java/TinyintType/hash
class TinyintType:    public static long hash(byte value)
    {
        // xxhash64 mix
        return rotateLeft(value * 0xC2B2AE3D27D4EB4FL, 31) * 0x9E3779B185EBCA87L;
    }