课程名称：计算机组织与结构
课程性质：必修
课程范围：第一至第四章
开课教师：徐国伟
开课学院：理学院
开课系级：资科三
考试日期(年月日)：2012/11/23
考试时限(Mins)：3小时
附注：
可以带计算机 (能不能带字典我忘了,好像可以?)
试题本文：
Q1.[25 points] Choose the best answer for each of the following multiple choice
questions. Justify your answers when necessary.
1. Which one of the following descriptions is correct?
(a) An instruction is a command that computer hardware understands and obeys.
(b) An assembly language is a symbolic representaion of machine instructions.
(c) A machine language is a binary representation of machine instructions.
(d) All of the above.
(e) None of the above.
2. Which one of the following descriptions about instruction set architecture
(ISA) is true?
(a) It is an abstract interface between the hardware and the lowest-level soft-
ware that encompasses all the information necessary to write a machine language
program that will run correctly.
(b) It allows computer designers to talk about functions independently from the
hardware that performs them.
(c) Maintaining it as a constant enables many implementation of that archi-
tecture - presumably varying in cost and performance - to run identical soft-
ware.
(d) All of the above.
(e) None of the above.
3. Which one of the following descriptions about how the hardware and software
affect performance is true?
(a) All algorithm, programming language, compiler, and instruction set archi-
tecture may affect instruction count.
(b) All algorithm, programming language, compiler, and instruction set archi-
tecture may affect CPI (clock cycles per instruction).
(c) Only instruction set architecture affects clock rate.
(d) All of the above.
(e) None of the above.
4. Which one of the following descriptions about performance is true?
(a) Execution time is the only valid and unimpeachable measure of performance.
(b) We should always expect the imporvement of one aspect of a computer to in-
crease overall performance by an amount proportional to the size of the im-
provement.
(c) We should always measure performance based on one of clock rate, in-
struction count, or CPI; that is, we should always use a subset of the perfor-
mance equaation as a performance metric.
(d) All of the above.
(e) None of the above.
5. Which one of the following descriptins about instructions is true?
(a) More powerful instructions mean higher performance.
(b) Write in assembly language to achieve the highest performance.
(c) The importance of commercial binary compatibility means successful
instuction sets do not change.
(d) All of the above.
(e) None of the above.
Q2. [10 points] The figure given below is the abstraction of the organization
of a computer discussed in class, showing the five classic components of a com-
puter. What are they (1, 2, 3, 4, and 5 in the figure) respectively? You need
to clarify which one is which.
(请参考课本的图,即有input、output、datapath、memory的图,每章一开始的那张图)
Q3. [10 points] Consider two different implementations of the same instruction
set architecture. There are four classes of instructions, A, B, C, and D. The
clock rate and CPI of each implementation are given in the following table.