Colin, Maybe I'm preaching to the choir. If so, please ignore :-)
Please don't confuse using 64-bit registers with running in amode 64. These are independent of one another. When running in amode 31 or 24 you can still use the full set of 64-bit instructions available on your hardware. Obviously, for modal instructions such as LA, the behaviour of the instruction will vary depending on the amode in effect at the time of execution. Kind regards, Abe Kornelis ========== Op 28/06/2022 om 18:03 schreef Colin Paice: > 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
