todo

基于组件方式开发操作系统的OSKIT源代码

sort by number of atoms (longest match of a form).

must find offset upto next shift and check against it.
	- actually, do we need to keep a list?

NEED TO DO:
	+ use different hash functions.
	+ chop vcode down so the fucking linker doesn't pull in the
		world.
	+ biggest code gen optimization: provide a gp register so we
		don't have to load pointer immediates.
	+ schedule across atoms.
	+ Fix vcode so the 16 bit-offset problem, isn't.

Done:

	+ Fix vcode so that returns don't rely on 16 bit offsets.
 	+ rehash when collisions
	+ optimize for no collisions
	+ optimize for all terminals
	+ Implement incremental compilation.
	+ don't regenerate code if no modification happens.
		need to expand to all cases where we don't need to
		regenerate all code (incremenally link in additions).

	+ special case no collisions in ht

	+ special case all terms in ht

on the alpha at least, linking is taking 50% of the time.  should 
look into eliminating the need for so many labels.  (Could have
destructive links... or push pop style links i suppose canonicallized
for ors, etc).