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Re: "Using" statement?

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John W Kennedy <jwkenne@attglobal.net> wrote:

> On 2012-07-13 12:12:09 +0000, Fritz Wuehler said:
> 
> > John W Kennedy <jwkenne@attglobal.net> wrote:
> > 
> > Didn't see Pete's post since I killfile everything from google
> > 
> >> On 2012-07-12 15:36:32 +0000, Pete Nelson said:
> >> 
> >>> On Friday, July 6, 2012 10:24:16 AM UTC-5, John W Kennedy wrote:
> >>>> But, as I say, if you are writing code expressly for z/Architecture,>
> >>>> and use only the Branch Relative family of instructions, and put all>
> >>>> your data in a separate CSECT or DSECT (or PSECT), you do not need a>
> >>>> base register for your code CSECT. That&#39;s why the Branch Relative>
> >>>> instructions were invented -- so that you have one more general>
> >>>> register to use for other purposes.
> >>>> 
> >>> Basically true, although whether your literal pool and constants are in
> >>> a separate CSECT or the same CSECT as your executable code, a base
> >>> register is still needed to address the data.  For small programs, you
> >>> probably end up using just as many base registers either way; when the
> >>> size of your executable code approaches/exceeds 4K, then you start
> >>> avoiding register starvation by using relative branching.
> > 
> > It's true many people allocate additional base registers when code exceeds
> > 4K but there is another way around this and I have written and worked on
> > substantial pieces of code that use one code base register no matter how
> > large the CSECT. There is really no excuse to use more than one code base
> > register, and I am saying that in reference to OS/360, not just since the
> > branch relative and immediate facility came out.
> 
> Back in the OS/360 days, frankly, I always regarded more than one code 
> base register (for which I generally used GR12 unless in a PL/I 
> environment, in which case I used GR11) as a sure sign that the module 
> had grown too big, and needed to be refactored.

Agreed. 

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"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

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