Scalar vectoring code does not always work (certain where clause values combo)

use test;

drop table if exists t;

create table t(c6 CHAR(6)) engine=columnstore;

insert into t(c6) values ('a'), ('b'), ('c');

select count(*) from t where (c6 <= 'b' or c6 is null);

The query returns 3 instead of 2.

internal note
We have two code paths for filtering: scalar and vectorized. Vectorized one is preferred and scalar one is used as fallback.

The following little snippet works differently when executed with vectorized code enabled and disabled: