Performance bottleneck for SQL Table-Valued Function for CSVtoTable

I am working on a query where I need to convert a CSV value holding few ID's sepearated by ,.

Currently I am using a Table-Values Function taken from here:

SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO
ALTER FUNCTION [dbo].[CSVToTable] (@InStr VARCHAR(MAX))
RETURNS @TempTab TABLE
   (id int not null)
AS
BEGIN
    ;-- Ensure input ends with comma
    SET @InStr = REPLACE(@InStr + ',', ',,', ',')
    DECLARE @SP INT
DECLARE @VALUE VARCHAR(1000)
WHILE PATINDEX('%,%', @INSTR ) <> 0 
BEGIN
   SELECT  @SP = PATINDEX('%,%',@INSTR)
   SELECT  @VALUE = LEFT(@INSTR , @SP - 1)
   SELECT  @INSTR = STUFF(@INSTR, 1, @SP, '')
   INSERT INTO @TempTab(id) VALUES (@VALUE)
END
   RETURN
END
GO

I use it in my view like this:

Select * from SomeTable S where ID in (Select * from CSVtoTable(S.CSVIDs))

Now I already know that this is going to cause performance issues when operating on a large number of rows in dataset i.e. > 1000. Because the function stores the parsed data to a Table variable, and in case of the same function being called 5 times for every row, will definitely cause issues.

Question: Is there any way to modify the code for better performance? Better if the same is being called in the view itself.

Update : Adding visual of sample data for reference

SQL server version I am running is:

Microsoft SQL Azure (RTM) - 12.0.2000.8 

Here is one option where you concatenate the 5 columns and call a more efficient parser once.

Example

Declare @YourTable Table ([N_ID] varchar(50),[CSVIDs] varchar(50),[Bar] varchar(50),[Lorem] varchar(50),[Ipsum] varchar(50))

Insert Into @YourTable 
Values (264, '2,3,4', '1,2,3', '1,2,6', '1,2,3'),
       (265, NULL, NULL, '1,2', NULL)

Select A.* 
From @YourTable A
Cross Apply [dbo].[tvf-Str-Parse-8K] (concat(CSVIDs,',',Bar,',',Lorem,',',ipsum),',') B
Where RetVal = 6

Returns

N_ID    CSVIDs  Bar     Lorem   Ipsum
--------------------------------------
264     2,3,4   1,2,3   1,2,6   1,2,3

The UDF if Interested:

CREATE FUNCTION [dbo].[tvf-Str-Parse-8K] 
    (@String VARCHAR(MAX), @Delimiter VARCHAR(25))
RETURNS TABLE
AS
    RETURN (  
        WITH cte1(N) AS
        (
            SELECT 1 
            FROM (VALUES (1), (1), (1), (1), (1), (1), (1), (1), (1), (1)) N(N)
        ),
        cte2(N) AS
        (
             SELECT TOP (IsNull(DataLength(@String), 0)) 
                 ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) 
             FROM
                 (SELECT N = 1 
                  FROM cte1 a, cte1 b, cte1 c, cte1 d) A 
        ),
        cte3(N) AS 
        (
             SELECT 1 
             UNION ALL 
             SELECT t.N + DataLength(@Delimiter) 
             FROM cte2 t 
             WHERE Substring(@String, t.N, DataLength(@Delimiter)) = @Delimiter
        ),
        cte4(N,L) AS 
        (
             SELECT S.N, ISNULL(NULLIF(CharIndex(@Delimiter, @String, s.N), 0) -S.N, 8000) 
             FROM cte3 S
        )
        SELECT
            RetSeq = ROW_NUMBER() OVER (ORDER BY A.N),
            RetVal = LTRIM(RTRIM(SUBSTRING(@String, A.N, A.L)))
        FROM
            cte4 A
    );
    -- Original Source http://www.sqlservercentral.com/articles/Tally+Table/72993/
--Select * from [dbo].[udf-Str-Parse-8K]('Dog,Cat,House,Car',',')
--Select * from [dbo].[udf-Str-Parse-8K]('John||Cappelletti||was||here','||')