I interpreted "might have taken pages of assembler instructions" as referring to GETMAIN, FREEMAIN and linkage needed in conjunction with the BALR. With PC/PR the registers are saved and restored with no additional user code.
-- Shmuel (Seymour J.) Metz http://mason.gmu.edu/~smetz3 ________________________________________ From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> on behalf of Peter Relson <rel...@us.ibm.com> Sent: Friday, August 30, 2019 8:24 AM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: Assembler :- PC Instruction <snip> >From what I understood of the PC instruction: with 1 instruction you can now execute a 'function' that might have taken pages of assembler instructions before. </snip> I'm not sure where this thought comes from. The PC instruction is not magic. It does not execute a "function" beyond the function of the instruction itself. It passes control somewhere, may change state, may create an entry on the linkage stack. Peter Relson z/OS Core Technology Design ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
