presto-main/src/main/java/io/prestosql/cost/FilterStatsCalculator.java/FilterStatsCalculator/filterStats
class FilterStatsCalculator:    public PlanNodeStatsEstimate filterStats(
            PlanNodeStatsEstimate statsEstimate,
            Expression predicate,
            Session session,
            TypeProvider types)
    {
        Expression simplifiedExpression = simplifyExpression(session, predicate, types);
        return new FilterExpressionStatsCalculatingVisitor(statsEstimate, session, types)
                .process(simplifiedExpression);
    }