Description of stackopt.scm

Purpose:
--------
STACKOPT attempts to reduce stack thrashing by examining temporaly
contiguous stack frames and attempting to make their layout as similar
as possible so that as few elements as possible need to be moved from
one stack slot to another.

There is more indepth documentation in stackopt.scm

[
In a CALL if the continuation matches a %make-stack-closure with a non
lambda expression then it returns as the continuation a CALL using 
%make-stack-lambda. otherwise it goes to the general case 
 (if the call-fram-vector
and the cont-fram-vector are the same the the case should be handled 
specialy because like in the case of non-lambda expression the stack 
has variables that cannot be moved. ) it uses %make-stack-closure
and %fetch-stack-closure and makes the state false so that it can
do the next step.
(when state is false) The common names that are in a frame and its 
descendents are maped to a fixed stack offset. so that to minimize moving 
them from one memory location to the other and having to load them 
and save them many times. other variables are assigned to free places
]
Operators Introduced:
---------------------
%make-stack-closure to be used in the cont which matches a pattern 
	containing it.

%fetch-stack-closure to be used in the cont of a lambda expression

Restrictions on Input:
----------------------
Special forms excluded: 
  ACCESS, DEFINE, DELAY, IN-PACKAGE, OR, SET!, THE-ENVIRONMENT
  UNASSIGNED?

Special forms introduced:
-------------------------
  none

Magic Cookies handled specially:
-------------------------------
%make-stack-closure contained in fixed locations that cannot be changed 
	at a given point in the computation.

%fetch-stack-closure is used to see whether the cont matches a pattern 
	containing it in order to get the proper layout.

Guarantees on Output:
---------------------
 none