presto-spi/src/main/java/io/prestosql/spi/type/RealType.java/RealType/hash
class RealType:    @Override
    public long hash(Block block, int position)
    {
        // convert to canonical NaN if necessary
        return hash(floatToIntBits(intBitsToFloat(block.getInt(position, 0))));
    }