You're right - there has to be a predetermined breakpoint but in my case I use 
it for testing X'40' or X'00' in strings and then do what I need to do after 
that.  Recently I have used a mix of SRST and TRT in the same program but they 
were used to perform a lot of different parsing.

-----Original Message-----
From: IBM Mainframe Assembler List [mailto:ASSEMBLER-LIST@LISTSERV.UGA.EDU] On 
Behalf Of Paul Gilmartin
Sent: Tuesday, October 18, 2016 11:30 AM
Subject: Re: SRST Performance (was: converting character to packed

On 2016-10-18, at 10:11, Martin Truebner wrote:
> TRT does a lockup for each and every char until terminating char is 
> found or the maximum length is reached- the lockup is done against a 
> table of 256 char.
Caching helps a lot.  How can the programmer insure that the table occupies the 
minimum number of cache lines?

Does modern hardware optimize this further?

> SRST does a check of each char against a single char (plus the 
> termination char).
Testing for multiple characters (e.g. non-numeric) requires multiple executions 
of of SRST.  Is there a break-even point with TRT?
Again, caching the subject string helps.

And the next hardware model will change the rules.

-- gil

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