presto-spi/src/main/java/io/prestosql/spi/block/AbstractSingleMapBlock.java/AbstractSingleMapBlock/compareTo
class AbstractSingleMapBlock:    @Override
    public int compareTo(int position, int offset, int length, Block otherBlock, int otherPosition, int otherOffset, int otherLength)
    {
        position = getAbsolutePosition(position);
        if (position % 2 == 0) {
            return getRawKeyBlock().compareTo(position / 2, offset, length, otherBlock, otherPosition, otherOffset, otherLength);
        }
        else {
            return getRawValueBlock().compareTo(position / 2, offset, length, otherBlock, otherPosition, otherOffset, otherLength);
        }
    }