With the 2-bit predictor, what speedup would be achieved if we could convert half of the branch instructions in a way that replaced each branch instruction with two ALU instructions? Assume that correctly and incorrectly predicted instructions have the same chance of being replaced.

The importance of having a good branch predictor depends on how often conditional branches are executed. Together with branch predictor accuracy, this will determine how much time is spent stalling due to mispredicted branches. In this exercise, assume that the breakdown of dynamic instructions into various instruction categories is as follows:

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a. b. a. R-Type b. 40% 60% BEQ 45% 65% 25% 8% Also, assume the following branch predictor accuracies: Always-Taken JMP 5% 2% Always-Not-Taken 55% 35% LW 25% 20% 2-Bit 85% 98% SW 5% 10%