Suppose the return address is loaded into R14 instead of a link type 
instruction and R14 points to the first byte of a page....

In addition, when a program is attached, R14 usually points to CVTEXIT (SVC 3) 
and the halfword before it is some vector value.

Keith Moe
BMC Software, Inc.


     On Tuesday, August 11, 2020, 03:01:48 PM PDT, Charles Mills 
<charl...@mcn.org> wrote:  
 
 > Too clever by far.  

Truer words have never been spoken.

Charles


-----Original Message-----
From: IBM Mainframe Assembler List [mailto:ASSEMBLER-LIST@LISTSERV.UGA.EDU]
On Behalf Of Farley, Peter x23353
Sent: Tuesday, August 11, 2020 11:33 AM
To: ASSEMBLER-LIST@LISTSERV.UGA.EDU
Subject: Re: how to return?

Too clever by far.  Offhand I don't think I would give it a passing grade in
a code review.

I can't immediately think of situations where it might fail, but I have the
sneaking suspicion that what I don't know (and that's a lot) could bite that
code.

Peter

-----Original Message-----
From: IBM Mainframe Assembler List <ASSEMBLER-LIST@LISTSERV.UGA.EDU> On
Behalf Of Ed Jaffe
Sent: Tuesday, August 11, 2020 2:15 PM
To: ASSEMBLER-LIST@LISTSERV.UGA.EDU
Subject: Re: how to return?

Clever...

On 8/11/2020 10:57 AM, Tony Thigpen wrote:
> I came across the following code today. The program can either be 
> called by JCL or from either an HLL or assembler program. While I 
> included some extra code for clarity, the code I am asking for 
> comments on is the code that 'fixes' R14 so that a BSM can be used 
> instead of a BR. I just thought I would ask what others think about 
> this method.
  

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