Agner Fog designed a new instruction set architecture described in detail here:
https://raw.githubusercontent.com/ForwardCom/manual/master/forwardcom.pdf (https://raw.githubusercontent.com/ForwardCom/manual/master/forwardcom.pdf)
The assembly language is C-like. There are some tools for it. Not a C compiler yet.
For more information see the dedicated website https://www.forwardcom.info/ (https://www.forwardcom.info/)
So it's a pretend instruction set.
Wonder if it'll ever be etched in silicon, or just be another interesting but forgotten computer-technology oddity.
I notice that his instruction set includes floating-point operations, as well as a lot of vector manipulation. Very nice.
By the way, I think the author is not right that it "is neither RISC nor CISC". IMHO it is really CISC, since memory operands are not limited to load and store instructions, and (because of that) the instruction length is variable.