I have been out of the office and half-following this thread on my phone. If it
were I, I think I would do the most straightforward thing:
LOOP EQU *
CLI MASK.FIELD1,'*'
JE Wild1
CLC MASK.FIELD1,TABLE.FIELD1
JNE LOOPX
Wild1 EQU *
CLI MASK.FIELD2,'*'
Etc.
J Found
LOOPX EQU *
* Bump to next table entry
J LOOP
Do the field most likely to be unequal first, then the second most likely, and
so forth. If the first field is unequal 90% of the time then you have a pretty
tight loop: CLI/JE/CLC/JNE/Bump.
And if I had a performance problem, only then would I attempt to address it.
Charles
-----Original Message-----
From: IBM Mainframe Assembler List [mailto:[email protected]] On
Behalf Of Tony Harminc
Sent: Tuesday, June 20, 2017 11:10 AM
To: [email protected]
Subject: Re: Table Searchig with a Mask
On 20 June 2017 at 12:13, Gary Weinhold <[email protected]> wrote:
>
> But since the "*"s to indicate a wild card are at fixed locations in
> the table, a CLI should be better performance than TR or TRT.
And depending on the numbers of Structure and Array entries, and the number of
*'d elements, it may well make sense to perform the single-instruction compare
(CLC?) first, and look at the *s only if that compare fails. It's pretty much
impossible to choose the right algorithm in the absence of the numbers of these
various items.
Tony H.
