Each optimisation pass is contained in a subdirectory of Opt/.
The main logic of the pass should be contained in the walk.scm
file.
Passes rely on Bigloo's object system for their implementation. This
architecture is inspired by the one of the Bigloo compiler itself. The
different classes of instruction are described in Ast/node.scm.
Each optimisation pass, then, is coded with generic functions
and methods. See the Opt/Unreachable
or Opt/Peephole passes for readable examples.