The new revision should address the latest batch of comments.
Also, the validator found the first potential bug: in SM1, opcode DCL apparently expects two sources, but they were not being parsed (nor, evidently, used). The outcome was that the corresponding entries in `src` were not initialised, and had random values which triggered the validator. I am not sure what the correct fix for that it. For the moment I just pretend that DCL in VSIR doesn't have any source (I see the validator as an internal thing, so if those sources are eventually found out to mean something, we can change the convention and the validator).