9. (10 points) Compilers can have a profound impact on the performance of an application. The following questions examine the relationship between dynamic instruction count, CPI, and clock rate in the context of two different compilers:

(a) Assume that for a given program, compiler A results in a dynamic instruction count of 8 108 and has an execution time of 1.1 seconds, while compiler B results in a dynamic instruction

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count of 1.2109 and an execution time of 1.6 seconds. Find the average CPI for each program given that the processor has a clock cycle time of 1ns.

2. (b) Assume the compiled programs run on two different processors with different clock rates. If the execution times on the two processors (one running compiler As code and the other running compiler Bs code) are the same, what is the ratio of the clock rate of the processor running compiler As code over the clock rate of the processor running compiler Bs code? Use the dynamic instruction count and calculated CPI from the previous part.

3. (c) A new compiler is developed that has a dynamic instruction count of only 7.5108 instructions and has an average CPI of 1.3. What is the speedup of using this new compiler versus using compiler A or B on the original processor?