SIM5 Thought Questions

The following questions assume that you are designing a new and improved SIM6 instruction 
set. You should indicate whether your new instructions are backward compatible or not and 
justify your decision. Similarly, if your new instructions eliminate any functionality of 
SIM5 instructions, you should justify your decision

1.	The skip instructions with format 7n0s have an unused digit (0) in the third 
position. Can you suggest one or two useful ways to use this digit to make the 
family more “powerful” without losing any currant functionality?

2.	The single register instructions with format 8n0d or 8n0s also have an unused digit 
in the third position. Can make good use of this digit for any or all of the single 
register family.

3.	The two instruction family (9nsd) has three open slots for new instructions. Which 
three instructions would you add (and why did you pick those three).

4.	It would be convenient to have a call instruction with a one digit op code followed 
by a three digit address so that the address of the function is included in the call 
statement. This would allow the statements “lda mult, call %r0: to be replaced with 
“call mult”. Can you find several alternative ways to implement . call mult” by 
revising the SIM5 instruction set. Select the alternative that you think is “best” 
and explain why it is best.