How do I change the latency of an instruction in gem5?

Question

I could access the latency of the dram but I could not find the latency of the instructions for the matrix multiplication in gem5. I have found the OpClass.hh and the file containing the all the classes but I cannot trace back to the instructions which have the latency and the parameters set. I want to change the latency and cycles of the instructions (classes)

Answer 1

You can modify the FuncUnitConfig.py to set instruction latency, see:https://github.com/gem5/gem5/blob/stable/src/cpu/o3/FuncUnitConfig.py.

If it doesn't meet your need, you can define your subclass of FUDesc and FUPool in o3/FUPool.py.