Function expr::relation::canonicalize::replace_subexpr_and_reduce

fn replace_subexpr_and_reduce(
    predicate: &mut MirScalarExpr, 
    replace_if_equal_to: &MirScalarExpr, 
    replace_with: &MirScalarExpr, 
    input_type: &RelationType
) -> bool

Replace any matching subexpressions in predicate, and if predicate has changed, reduce it. Return whether predicate has changed.