[libre-riscv-dev] multi-in. multi-out pipeline

[Luke Kenneth Casson Leighton]

got it!  amazing, actually worked.  complicated as hell, and made the
*Pipeline code look like a dog's dinner, stirred with a stick.

so i have an idea: create a separate (combinatorial) "not-a-pipeline"
that would be put *in between* pipeline stages, as
just-another-pipeline, conforming to the same valid/ready/data API.

that way the BufferedPipeline and UnbufferedPipeline classes remain
simple, straightforward, and obvious to understand.

thoughts?

l.