presto-main/src/main/java/io/prestosql/operator/JoinHash.java/JoinHash/getNextJoinPosition
class JoinHash:    @Override
    public final long getNextJoinPosition(long currentJoinPosition, int probePosition, Page allProbeChannelsPage)
    {
        if (positionLinks == null) {
            return -1;
        }
        return positionLinks.next(toIntExact(currentJoinPosition), probePosition, allProbeChannelsPage);
    }