Branch Prediction Simulator

• This simulator implements various branch predictors, including simple 1-bit and 2-bit predictors, as well as correlating (m,n) predictors
• We will utilize two sets of traces collected from a run of gcc. The traces gcc-10K.txt, and gcc-8M.txt and contain ~10 thousand and ~8.5 million entries respectively
• A simple 1-bit predictor is (0,1) predictor and simple 2-bit predictor is (0,2) predictor with 0 global history. Therefore, the simulator takes as input a branch predictor type in the form of (m,n).

Executing the script

$ python branchsim.py -f [filename] -n [n] -m [m] -k [k]

• m is global branch history and takes value in the range (0-11)
• k is the number of LSB bits of PC and takes value in the range (1-12)
• n is the branch predictor type and takes value 1 or 2
• f input file name
• Default values for m,n and k are 6, 1 and 8 respectively

Example

• (6,1) branch predictor

$ python branchsim.py -f gcc-10K.txt -n 1 -m 6 -k 8

• 1-bit predictor (0,1)

$ python branchsim.py -f gcc-10K.txt -n 1 -m 0 -k 8

• 2-bit predictor (0,2)

$ python branchsim.py -f gcc-10K.txt -n 2 -m 0 -k 8