Branch prediction, accuracy and impact. The CPI for an ideal 5-stage pipeline that is always full...

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Branch prediction, accuracy and impact. The CPI for an ideal 5-stage pipeline that is always full is 1. Assume a code with no data hazards, and no delay slots are used, but with 25% of branch instruction. Assume that branch outcomes are determined in the ID stage and a misprediction causes a cycle delay. Also assume the following branch predictor accuracies. Always-Taken 45% Always-Not-Taken 55% 2-Bit 85% a. [5pts]Stall cycles due to mispredicted branches increase the CPI. What is the extra CPI due to mispredicted branches with the always-taken predictor? b. [5pts]What is the extra CPI due to mispredicted branches with the always-not-taken predictor? c. [5pts] What is the extra CPI due to mispredicted branches with the 2-bit predictor? Branch prediction, accuracy and impact. The CPI for an ideal 5-stage pipeline that is always full is 1. Assume a code with no data hazards, and no delay slots are used, but with 25% of branch instruction. Assume that branch outcomes are determined in the ID stage and a misprediction causes a cycle delay. Also assume the following branch predictor accuracies. Always-Taken 45% Always-Not-Taken 55% 2-Bit 85% a. [5pts]Stall cycles due to mispredicted branches increase the CPI. What is the extra CPI due to mispredicted branches with the always-taken predictor? b. [5pts]What is the extra CPI due to mispredicted branches with the always-not-taken predictor? c. [5pts] What is the extra CPI due to mispredicted branches with the 2-bit predictor?

Answer rating: 100% (QA)

a With the alwaystaken branch predictor the extra CPI due to mispredicted branches can be calculated ... View the full answer