Not a whole lot of work done, but I have been working on documentation lately. I've put together some notes on dynamically-loaded libraries, and system calls in general. I think it could work, and thinking down these lines is helpful for later.
I've also put together some notes for my modifications to the GAS assembler. I was thinking about the fact that I don't have an Editor/Assembler manual, and that it would probably help to ask around to get the missing pieces. In order for someone else to see my gaps, I need to document what I have so far.
The assembler documentation is very sparse, but I think it's a decent start.
While digging around for more info, I found the "nop" and "rt" pseudo-ops in example code in a couple places, so that seems legitimate. "Nop" is encoded as "jmp 0" and "rt" as "b *r11". While I was in there, I added "or" and "orb" as aliases for "soc" and "socb" since I can't ever remember the real instructions.
I had problems adding these instructions, since I made a dumb mistake in the parser. I was assuming there was an argument, and skipping the intervening space. This resulted in skipping the null terminator for the line, and getting "junk at end of line" errors. This has been fixed.