Exercise 5.12: The simulator can be used to help
determine the data paths required for implementing a machine with a given
controller.  Extend the assembler to store the following information in the
machine model:


 a list of all instructions, with duplicates removed, sorted by instruction type
(assign, goto, and so on);

 a list (without duplicates) of the registers used to hold entry points (these
are the registers referenced by goto instructions);

 a list (without duplicates) of the registers that are saved
or restored;

 for each register, a list (without duplicates) of the sources from which it is
assigned (for example, the sources for register val in the factorial
machine of Figure 5.11 are (const 1) and ((op *) (reg n)
(reg val))).



Extend the message-passing interface to the machine to provide access to this
new information.  To test your analyzer, define the Fibonacci machine from
Figure 5.12 and examine the lists you constructed.