Groups | Search | Server Info | Login | Register

Groups > comp.lang.asm370 > #48

Re: "Using" statement? - reply

Show all headers | View raw

Fritz Wuehler wrote:
> JEmebius <jemebius@xs4all.nl> wrote:
> 
>> When I knew in advance that my OS/360 module would occupy more than 8 Kbytes (4096 bytes) and 
>> certainly less than 12 Kbytes I would define registers GR12, GR11 and GR10 as base registers for the 
>> first 4K, the second 4K and the last 4K, and load them in advance with the appropriate values:
>> <GR15>, <GR15> + 4096, <GR15> + 8192.
> 
> This is unnecessary and wasteful. There isn't any reason you need more than
> one code base register, no matter how large the program is. Break the
> program into functional routines, branch-enter those as needed, and readjust
> the base register as needed to cover only the current routine.
> 
>> (Takes 18 bytes)
> 
> But wastes 2 registers for no good reason.
> 


My thanks for your comment.
I guess you think of subdividing large programs into CESCTs needing only one base register; correct 
guess?
Of course this is a good guideline, but it is a guideline only, not a prescription cut in stone.

I know disciplines of designing and programming. A few times I followed the base register tactics 
you explained. Once in a while it is next to impossible, or indeed quite impossible, to break up the 
coding into functional parts of 4 Kbytes or smaller. In such cases multiple base registers are far 
more practical than artificially subdividing the code into small subroutine-like pieces.

We could set up a philosophical discussion on the concepts of necessity and wastefulness in computer 
programming versus the same concepts in real life. In my opinion an inconsequential discussion, a 
non-issue.

Ciao: Johan E. Mebius

Back to comp.lang.asm370 | Previous | Next — Previous in thread | Next in thread | Find similar

Thread

"Using" statement? hancock4@bbs.cpcn.com - 2012-07-06 06:52 -0700
  Re: "Using" statement? John W Kennedy <jwkenne@attglobal.net> - 2012-07-06 11:24 -0400
    Re: "Using" statement? hancock4@bbs.cpcn.com - 2012-07-06 10:15 -0700
    Re: "Using" statement? Fritz Wuehler <fritz@spamexpire-201207.rodent.frell.theremailer.net> - 2012-07-12 07:31 +0200
      Re: "Using" statement? John W Kennedy <jwkenne@attglobal.net> - 2012-07-12 22:09 -0400
    Re: "Using" statement? Pete Nelson <plnelsonoma@yahoo.com> - 2012-07-12 08:36 -0700
      Re: "Using" statement? John W Kennedy <jwkenne@attglobal.net> - 2012-07-12 22:13 -0400
        Re: "Using" statement? Fritz Wuehler <fritz@spamexpire-201207.rodent.frell.theremailer.net> - 2012-07-13 14:12 +0200
          Re: "Using" statement? John W Kennedy <jwkenne@attglobal.net> - 2012-07-13 13:57 -0400
            Re: "Using" statement? Anonymous <noreply@breaka.net> - 2012-07-15 05:54 -0400
              Re: "Using" statement? -  JEmebius <jemebius@xs4all.nl> - 2012-07-30 22:09 +0100
                Re: "Using" statement? -- JEmebius <jemebius@xs4all.nl> - 2012-07-30 22:13 +0100
                Re: "Using" statement? --- JEmebius <jemebius@xs4all.nl> - 2012-07-30 22:19 +0100
                Re: "Using" statement? --- woodag@trap.ozemail.com.au (Andy Wood) - 2012-07-31 06:22 +0000
                Re: "Using" statement? --- reply JEmebius <jemebius@xs4all.nl> - 2012-08-01 02:44 +0100
                Re: "Using" statement? - Fritz Wuehler <fritz@spamexpire-201207.rodent.frell.theremailer.net> - 2012-07-31 20:46 +0200
                Re: "Using" statement? - reply JEmebius <jemebius@xs4all.nl> - 2012-08-01 03:10 +0100
                Re: "Using" statement? - reply Fritz Wuehler <fritz@spamexpire-201208.rodent.frell.theremailer.net> - 2012-08-07 16:36 +0200
                Re: "Using" statement? - reply Nomen Nescio <nobody@dizum.com> - 2012-08-07 21:33 +0200
                Re: "Using" statement? - reply Clark F Morris <cfmpublic@ns.sympatico.ca> - 2012-08-07 18:13 -0300
                Re: "Using" statement? - "Michel Castelein" <arcis@advalvas.be.without.this.no.spam.tail> - 2012-08-03 11:13 +0200
                Re: "Using" statement? - Anonymous <nobody@remailer.paranoici.org> - 2012-08-03 13:05 +0000
                Re: "Using" statement? - Allodoxaphobia <knock_yourself_out@example.net> - 2012-08-03 13:29 +0000
                Re: "Using" statement? - WAB JEmebius <jemebius@xs4all.nl> - 2012-08-04 00:03 +0100
                Re: "Using" statement? - WAB Allodoxaphobia <knock_yourself_out@example.net> - 2012-08-04 03:14 +0000
                Re: "Using" statement? - Nomen Nescio <nobody@dizum.com> - 2012-08-06 15:15 +0200
  Re: "Using" statement? alistair.j.l.maclean@gmail.com - 2012-08-19 05:58 -0700
    Re: "Using" statement? John W Kennedy <jwkenne@attglobal.net> - 2012-08-19 13:15 -0400
      Re: "Using" statement? Nomen Nescio <nobody@dizum.com> - 2012-08-19 22:20 +0200
        Re: "Using" statement? John W Kennedy <jwkenne@attglobal.net> - 2012-08-19 18:30 -0400

csiph-web