From: Thomas Huth on
gitlab.com
https://gitlab.com/cki-project/kernel-ark/-/merge_requests/1144#note_5986...
If I've got that right, the z14 introduced the "Miscellaneous-Instruction-
Extensions Facility 2" which provides a bunch of new instructions:
* ADD HALFWORD (AGH)
* BRANCH INDIRECT ON CONDITION
* MULTIPLY (MG, MGRK)
* MULTIPLY HALFWORD (MGH)
* MULTIPLY SINGLE (MSC, MSGC, MSGRKC, MSRKC)
* SUBTRACT HALFWORD (SGH)
Not sure whether compilers will make use of this, though...