Add nested loops example in MIPS assembler

[pavelkryukov]

Proxy for MIPT-ILab/mips-traces#11

Two-level BP has much performance for prediction nested loops as it generates mispredicts only on loop exit. To demonstrate it, a simple trace with nested loops is required.

C pseudocode of the example:

   for (int i = 0; i < N; ++i) {
       for (int j = 0; j < M; ++j) {
           // <some action here>
       }
       // <some action here>
   }

[pavelkryukov]

Do you have any progress with that?

[iakovgi]

Yes, I'm working on that. Sorry for delay, there was some side work