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Word process all answers. Show work for partial credit.

1. Answer the following questions regarding the Intel x86 instruction set (refer to the figure on

slide 3 of the chapter 5 power point notes).

a. Assume the x86 architecture can fetch 32 bits per cycle and the x64 architecture can fetch

64 bits per cycle. In the best case, how many instructions can be fetched per cycle in the

x86 and how many instructions can be fetched per cycle in the x64? In the worst case, how

many cycles might it take the x86 to fetch one instruction and how many cycles might it

take the x64 to fetch one instruction? Best case means the shortest possible instruction

length and worst case means the longest possible instruction length.

b. What is the largest immediate datum available (not in bits but the largest value)?

Remember that the immediate datum is in two's complement.

c. How many registers are available to be used as index registers?

d. What is the maximum number of opcodes that could be accommodated in an instruction

(this is not the actual number, but the maximum that could be used)? The actual number

varies by generation with the original x86 having only 81 but later variations had as many

as 981.

Fig: 1