On Wed, 18 Jun 2025 11:13:19 -0500, Adam Johanson wrote: >Michael wrote: > >> On z/Architecture, are there instructions that the machine will execute that >> are not following the Principles of Operation documentation? Or would all >> such instructions get a specification exception? > Diagnose? I believe its existence is documented; otherwise, "model dependent". And no mnemonic.
>It's my understanding that millicode instructions are "real" instructions with >opcodes and such that are simply not documented. I also heard that they have >their own set of registers to use. > >Could be wrong, though. -- gil ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
