Okay, got it. The rules for a called program and the rules for the IBM macros 
are the same (except as otherwise explicitly specified):

- The high halves of R2 through R13 must go back as they arrived.
- The high halves of R14 through R1 are fair game. You can use a grande 
instruction or an IBM macro in your subprogram and not worry about restoring 
R14 through R1.

Charles

-----Original Message-----
From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf 
Of Tom Marchant
Sent: Monday, June 13, 2016 1:34 PM
To: [email protected]
Subject: Re: LINK and high order word of R1

On Mon, 13 Jun 2016 11:19:06 -0700, Charles Mills wrote:

>In the description of LINK in Assembler Services I read
>
>...
>
>Does that mean that for standard "old-fashioned" AMODE 31 72-byte savearea
>linkage I am obligated to save the high word of R1 before issuing LINK in a
>called program? If so, this would seem to be a compatibility issue for older
>code that uses LINK. Or is R1 fair game as a work register in a called
>program?

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