private void convertReferenceEqualityToValueEquality(DfaValue value) {
    int id = canonicalize(value).getID();
    int index = myIdToEqClassesIndices.getOrDefault(id, -1);
    if (index == -1) return;
    for (Iterator<DistinctPairSet.DistinctPair> iterator = getDistinctClassPairs().iterator(); iterator.hasNext(); ) {
      DistinctPairSet.DistinctPair pair = iterator.next();
      EqClass otherClass = pair.getOtherClass(index);
      if (otherClass != null && getDfType(otherClass.getVariable(0)) != DfTypes.NULL) {
        iterator.remove();
      }
    }
  }
private void convertReferenceEqualityToValueEquality(DfaValue value)