Chuck Moore / GreenArrays at Strange Loop 2013

I think this was my favorite bit of Strange Loop 2013. Chuck Moore (inventor of FORTH and other interesting things) spoke about his work at GreenArrays  on a novel CPU. The CPU consists of 144 separate “computers” those computers are quite small in capability compared what we typically think of as a computer or CPU. They are extremely RISC and startlingly efficient in terms of nanowatts per unit of computation. Chuck made a compelling case that a few years down the road this metric, energy expended relative to work done will become a main driver in system design.

2013-09-20 Strange Loop Chuck Moore2

Chuck is a low-level kind of guy, so he spent much of the talk discussing ways to program this array of tiny computers at the individual level. The techniques are quite radically different from any kind of programming I’ve ever heard of; for example it is necessary to make two or three of these tiny computers collaborate over a wire/channel between them merely to communicate with main memory! Also, these tiny computers have an unusual six-bit “byte” and 18 bit “word”.

Now the obvious thing to want here is a compiler. A compiler that takes a program written in a high-level language and emits an array of programs to run on this array of computers to achieve the high level program’s purpose. My understanding of the state-of-the-art in compiler design is woefully incomplete, but I’m fairly confident that the thing needed here is far beyond what anyone is doing. I can’t find much about this concept on the GreenArrays website, surprisingly. I wonder if there are any research projects attempting to build such a compiler. Certainly this would be an extreme case of the quest for a “sufficiently smart compiler“.