This directory contains the files for the compiler backend.  All of these
phases operate on FLIC code.

optimize -- performs various tweaks to compact the code and make it faster.
  also includes a postpass to fill in some additional structure slots.

strictness -- attaches strictness information to functions and decides
  whether locally-bound variables have a boxed or unboxed representation.

codegen -- generates Lisp code from the optimized FLIC code.