@Override
    public int hashCode() {
        int result = docId;
        result = 31 * result + (int) (subquery ^ (subquery >>> 32));
        return result;
    }
Represents a hit from the predicate search algorithm.
Each hit is associated with a subquery bitmap,
indicating which subqueries the hit represents.

@author Magnar Nedland
predicate-search/src/main/java/com/yahoo/search/predicate/Hit.java