For AMODE64 there is an inconsistency between CALL and supervisor-assisted linkage. The register setup for PGM=foo is the same as for any other ATTACHX of foo.
OS/360 loaded R15. DOS/360 did not. -- Shmuel (Seymour J.) Metz http://mason.gmu.edu/~smetz3 ________________________________________ From: IBM Mainframe Assembler List <[email protected]> on behalf of Paul Gilmartin <[email protected]> Sent: Monday, December 2, 2019 5:42 PM To: [email protected] Subject: Re: BASR to AMODE 64 On 2019-12-02, at 09:48:39, Ed Jaffe wrote: > > On 12/2/2019 7:58 AM, Kerry Liles wrote: >> Or >> >> LR 12,15 >> USING entrypointname,12 > > And, of course, R15 is not even loaded with the entry point address for > programs given control in AMODE(64) :-\ > That strikes me as thoughtless; bad design. High astonishment factor and breaks consistency between CALL and JCL EXEC. But what about bit 63? I've been told that some OSes: CMS? VSE? ancient OS/360? did not guarantee R15. > These days, one is expected to issue LARL/USING to your program constants. > There is generally no need whatever for base register coverage of the code. -- gil
