Scenario:

A program comprising $150$ instructions is executed on a processor with a $4-$stage pipeline. This pipeline encounters control hazards due to $20$ branch instructions. The processor utilizes a branch prediction technique with a $70\%$ accuracy rate, and each mispredicted branch incurs a $3-$cycle penalty due to the need to flush and refill the pipeline.

Task:

Calculate the total execution time of the program in cycles, considering the impact of control hazards from branch instructions, and compute the overall Cycles Per Instruction $($CPI$).$

Assumptions:

Total Instructions: $150$

Branch Instructions: $20$

Branch Prediction Accuracy: $70\%$

Misprediction Penalty: $3$ cycles

Calculations:

a$.$ Calculate the total number of cycles for instructions without considering control hazards.

b$.$ Determine the number of correctly predicted branches and

c$.$ the number of mispredictions.

d$.$ Calculate the additional cycles incurred due to mispredictions.

e$.$ Compute the total execution time by adding the base cycles and the penalty cycles.

f$.$ Calculate the overall CPI by dividing the total execution time by the number of instructions.