Hi Colin, You may want to check out MVS Programming: Assembler Services Guide https://www-40.ibm.com/servers/resourcelink/svc00100.nsf/pages/zOSV2R3sa231368/$file/ieaa600_v2r3.pdf And if you're running under LE, there will be a Language Environment pub or two that may provide some guidance. While probably not specifically addressing your issue, John Ehrman's text 'Assembler Language Programming for IBM System z Servers V2' is quite an excellent reference regarding the instructions and usage... http://zseries.marist.edu/enterprisesystemseducation/assemblerlanguageresources/Assembler.V2.alntext%20V2.00.pdf
HTH, Mike -----Original Message----- From: IBM Mainframe Assembler List <[email protected]> On Behalf Of Colin Paice Sent: Tuesday, June 28, 2022 12:04 PM To: [email protected] Subject: Documentation on the new 64 bit instructions Caution! This message was sent from outside your organization. I've been working on calling an assembler program from a 64 bit C program, and have been struggling.Is there is a good guide on how to use these new instructions? For example1) "You need to use a LLGTR R1... instruction to clear the register before using a L R1... because without it the high part of the register will have some 64 bit rubbish in it" 2) I used BAKR R14,0 PR But it kept returning in 24 bit mode. It needs BSM 14,0 before the BAKR.__ The POP tells you all about the instructions - but not how to use it. The z/OS doc says use BACK/PR without mentioning the BSM. Colin Paice
