## [IFT 201] Computer and Network Systems: Organization and Administration

26 Mar
 Homework Assignment 5

Show all your work.

Exercise I. Translating from Java Language to MIPS Assembly (5*3 = 15pts)

For the Java statements on the left, provide the corresponding MIPS assembly code in the corresponding space on the right. Assume f, g, and j are assigned to registers \$s0, \$s1, and \$s2 respectively, and h is assigned to register \$v0. Also assume that the starting address of the array A (which is an array of 15 words) is in register \$ra

 C statements MIPS Assembly code f = (g + h) + (j + 13) A[12] = h + A[8] if (j !=h ) f = f + 1; f = g + h;

Exercise II (2.5*4 = 10 pts)

We wish to compare two systems S1 and S2. The table below presents measurements for the two systems when running two programs, Program 1 and Program 2.

 System 1 System 2 Program ExT (sec) IC ExT (sec) IC 1 6 12×106 8 10×106 2 10 6

1. If the clock rate of system S1 is 4 MHz and the clock rate for system S2 is 6 MHz, find CPI For each system when running Program 1

CPI for S1 = ______________

CPI for S2 = ______________

1. Assuming the CPI for each system when running Program 2 is the same as it is when running Program 1, find the instruction count (IC) for each system when running Program 2

IC for S1 = ______________

IC for S2 = ______________

Exercise III (5*3 = 15 pts)

Consider a pipelined execution of the following program segment in which the instruction labeled “Beg” starts at memory address (2040)10. All registers used contain 0 initially.

 Beg: add \$8, \$9, \$10 beq \$5, \$6, Nex lw \$7, 30(\$13) sw \$14, 48(\$15) Nex : and \$11, \$12, \$13
1. Show the state of the 5-stage pipeline (i.e. the “pipelined execution representation”) for the instructions above.

1. Assume the time for stages is 100ps for register read or write, and 200ps for other stages. Compute the total time required for each of the instructions used in the program segment above.

1. Compare the total execution time for non-pipelined and pipelined execution of the above program segment:

Non-pipeline design = ______________ ps

Pipelined design = ______________ ps

_________________ design is _________ times faster