Yes! This tripped me up at one point. My comment says "Otherwise we could be in the bizarre special-case of 3-argument CMP instructions."

https://github.com/mmcloughlin/avo/blob/0e253b3753beb409b3dd...

It gets to the point where the only source of truth is the Go assembler itself. My test suite takes the avo instruction database and generates a massive assembly file with one line per instruction form, then passes this to `go tool asm`.