Description of laterew.scm

Purpose:
--------
LATEREW is a primitive rewrite stage that occurs after CPS conversion.
Branches introduced here will not create new lambda expressions, and
non-simple operators introduced here must be able to preserve the
relevant state when called.



Operators Introduced:
---------------------
%continue is used to represent the continuation.
%invoke-continuation if continuation is not a quote then it is CALLed
%stack-closure-ref if an operator is a CALL to it then error of unexpected 
continuation.
%+ 
%-
%*
%=
%<
%>
%quotient
%remainder

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

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

Magic Cookies handled specially:
-------------------------------
%fixop used if the operands are fixnum
%genop used if the operands are not numbers or fixnums.
%test used to determine which test of fixnum from below to use.

%small-fixnum?
%machine-fixnum? used to test if the operand is a fixnum then uses %fixop.


Guarantees on Output:
---------------------
 operators are rewritten without creating new lambda expretions, and non simple
operators must be able to preserve relevant state when called.