And you can thank Musial and Ehrman for being able to do that.
-- Shmuel (Seymour J.) Metz http://mason.gmu.edu/~smetz3 ________________________________________ From: IBM Mainframe Assembler List <[email protected]> on behalf of Charles Mills <[email protected]> Sent: Monday, November 11, 2019 2:38 PM To: [email protected] Subject: Re: Questionable Instructions in Obtaining EAX documentation Why not -- from memory; untested; I could be off -- but something like USING PSA,0 USING PSWDSECT,FLCIOPSW ? Does not burn a register for nothing. You can even name the DSECTs and have addressability on a couple of different low-memory PSWs at the same time OldIOPSW USING PSWDSECT,FLCIOPSW OtherPSW USING PSWDSECT,SOMEOPSW You address fields as L R2,OldIOPSW.PSWIADDR Charles -----Original Message----- From: IBM Mainframe Assembler List [mailto:[email protected]] On Behalf Of Paul Gilmartin Sent: Monday, November 11, 2019 11:10 AM To: [email protected] Subject: Re: Questionable Instructions in Obtaining EAX documentation On 2019-11-11, at 09:25:32, Jonathan Scott wrote: > > The USING 0 case used to occur from time to time by accident > when using PL/S, PL/X or similar compilers which generate > assembler as an intermediate step, if the programmer switched > into assembler temporarily. This was because the programmers > often failed to realise that the compiler translated a structure > to a set of equates for offsets, not a DSECT. > ... I once had a DSECT that mapped a PSW. So, hopefully, I tried something like: USING PSWDSECT-FLCIOPSW,R0 The result was not what I intended. Experts tell me the design is misguided, but won't be fixed lest it break extant art. Interestingly: XR R2,R2 USING PSWDSECT-FLCIOPSW,R2 works better and more intuitively. -- gil
