106年 - 106 國立中山大學_碩士班招生考試_電機系(己組)：計算機結構#108290

科目：中山◆電機◆計算機結構 | 年份：106年 | 選擇題數：0 | 申論題數：7

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所屬科目：中山◆電機◆計算機結構

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(Problem 1] (20%) Terminology Explanation

(a) Pipeline Processing (b) Superscalar Processor (c) RISC (d) GPGPU

(Problem 2] (20%)

Suppose we are considering a change to an instruction set. The base machine is a load-store machine. Measurements of the load-store machine showing the instruction mix and clock cycle counts per instructions are given in the following table:

Let's assume that 30% of the ALU operations directly use a loaded operand that is not used again. We propose adding ALU instructions that have one source operand in memory. These new register-memory instructions have a clock cycle count of 2. Suppose that the extended instruction set increases the clock cycle count for branches by 1, but it does not affect the clock cycle time. Would this change improve CPU performance? Explain your answer.

(Problem 3] (20%) A set associative cache has a block size of four 32-bit words and a set size of 4. The cache can accommodate a total of 256K words. The main memory size that is cacheable is 1024M * 32 bits. Design the cache structure and show how the processor's addresses are interpreted.

(1) Support add, sub, and sgt (set on great than) functions. Their operation selection bits (op_sel) are as follows: add(00), sub(10), sgt(11),

(2) Report the result status in sign, zero, overflow, and carry bits.

(a) (10%) Show the timing of this instruction sequence for the five-stage instruction pipeline with normal forwarding and bypassing hardware. Assume that branch is handled by predicting it has not taken. How many eycles does this loop take to execute?

(b) (10%) Assuming the five-stage instruction pipeline with a single-cycle delayed branch and normal forwarding and bypassing hardware, schedule the instructions in the loop including the branch-delay slot. You may reorder instructions and modify the individual instruction operands, but do not undertake other loop transformations that change the number of op- code of instructions in the loop. Show a pipeline timing diagram and compute the number of cycles needed to execute the entire loop.