Oops, Tony is correct – you can use LARL even if the exit labels are outside of the mainline USING I suggested.
That’s a much better solution than my adcon suggestion. If you decide to use my USING suggestions then change your LA’s to LARL’s for the exit addresses. Peter From: IBM Mainframe Assembler List <ASSEMBLER-LIST@LISTSERV.UGA.EDU> On Behalf Of Tony Harminc Sent: Wednesday, November 8, 2023 5:25 PM To: ASSEMBLER-LIST@LISTSERV.UGA.EDU Subject: Re: Internal Exit Routine Handling On Wed, 8 Nov 2023 at 17:13, Farley, Peter < 00000dc9d8785c29-dmarc-requ...@listserv.uga.edu> wrote: > The “why” of using adcons instead of direct instruction reference with my > suggested USING setup: > > Because the mainline USING that I suggested limits the use of R11 to just > the mainline code and data, the labels on your exit routines are not > addressable using R11 since they are outside of that range of addresses. > > Loading an A(exitname) constant means the assembler can resolve the adcon > value to “offset from start of code” because it knows where that name is in > the object code, but it won’t let you use that name directly in LA or LAY > because there is no base register that covers the area where the exit name > is coded. Then the loader can fully resolve the adcon value at program > load time because the ESD entry is “CSECT start + offset”. > In the case where the routines are in the same assembly/CSECT, but don't have addressibility via a register, LARL is your friend. For that matter LARL is generally useful in all sorts of such cases. For example, where you have a main routine and some sort of exits or callbacks that don't get passed the original base register value, in old-style coding you might need something like: BALR Rx,EXIT USING EXIT,Rx L Rn,=A(MAIN) USING MAIN,Rn to establish a base. Now you can use LARL Rn,MAIN USING MAIN,Rn to get the main base back. Tony H. -- This message and any attachments are intended only for the use of the addressee and may contain information that is privileged and confidential. If the reader of the message is not the intended recipient or an authorized representative of the intended recipient, you are hereby notified that any dissemination of this communication is strictly prohibited. If you have received this communication in error, please notify us immediately by e-mail and delete the message and any attachments from your system.
