Question

This exercise examines the accuracy of various branch predictors for the following repeating pattern (e.g., in a loop) of branch outcomes: T, NT, T, T, NT.
a. What is the accuracy of always-taken and always-not-taken predictors for this sequence of branch outcomes?
b. What is the accuracy of the 2-bit predictor for the first four branches in this pattern, assuming that the predictor starts off in the bottom left state (predict not taken)?
c. What is the accuracy of the 2-bit predictor if this pattern is repeated forever?

Answer 1

Answer:

attached below is the missing part of the question and the solution

A) 60%, 40%

B) 25%

C) 60%

Step-by-step explanation:

a) The accuracy of always-taken for this sequence of branch outcomes = 60%

The accuracy of always -not-taken for this sequence of branch outcomes = 40%

b) The accuracy of the 2-bit predictor for the first four branches assuming that the predictor starts off in the bottom left state = 25%

C)the accuracy of the 2-bit predictor if this pattern is repeated forever = 60% ( was stopped after the fourth iteration because the fourth and third iterations are the same)  =