presto-main/src/main/java/io/prestosql/type/BooleanOperators.java/BooleanOperators/isDistinctFrom
class BooleanOperators:        @SqlType(StandardTypes.BOOLEAN)
        public static boolean isDistinctFrom(
                @BlockPosition @SqlType(value = StandardTypes.BOOLEAN, nativeContainerType = boolean.class) Block left,
                @BlockIndex int leftPosition,
                @BlockPosition @SqlType(value = StandardTypes.BOOLEAN, nativeContainerType = boolean.class) Block right,
                @BlockIndex int rightPosition)
        {
            if (left.isNull(leftPosition) != right.isNull(rightPosition)) {
                return true;
            }
            if (left.isNull(leftPosition)) {
                return false;
            }
            return notEqual(BOOLEAN.getBoolean(left, leftPosition), BOOLEAN.getBoolean(right, rightPosition));
        }