presto-main/src/main/java/io/prestosql/sql/planner/DomainTranslator.java/DomainTranslator/extractEquatableDomain
class DomainTranslator:        private static Domain extractEquatableDomain(ComparisonExpression.Operator comparisonOperator, Type type, Object value, boolean complement)
        {
            checkArgument(value != null);
            switch (comparisonOperator) {
                case EQUAL:
                    return Domain.create(complementIfNecessary(ValueSet.of(type, value), complement), false);
                case NOT_EQUAL:
                    return Domain.create(complementIfNecessary(ValueSet.of(type, value).complement(), complement), false);
                case IS_DISTINCT_FROM:
                    // Need to potential complement the whole domain for IS_DISTINCT_FROM since it is null-aware
                    return complementIfNecessary(Domain.create(ValueSet.of(type, value).complement(), true), complement);
                default:
                    throw new AssertionError("Unhandled operator: " + comparisonOperator);
            }
        }