- What is the formula to determine the execution time of a program.
For each of the three terms in this formula, tell whether RISC
or CISC processors do a better job of minimizing the term.
 - If a program spends 25% of its running time doing integer
division, how much speedup would be achieved by adding hardware
that makes integer division run twice as fast?
 - How many bits are needed to provide addresses for a 128 KB
memory?
 - Describe the format of the MIPS slt instruction. Tell
the number of bits for each field, and what the instruction does.
 - Show the format of the MIPS bne instruction. Tell the
number of bits for each field, what the instruction does, and
how the branch target address is computed.
 - Show the format of the MIPS jmp instruction. Tell the
number of bits for each field, what the instruction does, and
how the branch target address is computed.
 - Draw the gates to implement a multiplexor with two control
inputs. Label all inputs and outputs.
 - Draw a diagram showing the internal structure of cell number
31 for the ALU designed in the textbook for a MIPS processor.
 - Tell the reason for implementing carry-lookahead logic. Give
the equations for carry generate and carry propagate and for C1
through C3.
 - Complete the given rows of the following truth table for the
four-bit parallel adder-subtracter designed in class. Answer on
this sheet. Notes: a/s is the add/subtract control (0 means
add), c is the carry out of the left-most bit, v
is the arithmetic overflow indicator, n is the negative
result indicator, and z is the zero result indicator. You
do not have to show the values for B' as we did in class.
 
A3 A2 A1 A0 B3 B2 B1 B0 a/s      C   V   N   Z   S3   S2   S1   S0         
0  1  1  1  1  0  0  1   0                                                 
0  0  1  0  0  1  1  0   1                                                 
0  1  1  1  0  1  0  0   0                                                 
Christopher Vickery
Computer Science Department
Queens College of CUNY