Section 5: Simulate the AI Engine graph using the aiesimulator and viewing trace, and profile results in Vitis Analyzer. - 2022.2 English

After the graph has been compiled, you can simulate your design with the aiesimulator command. This uses a cycle approximate model to test your graph and get preliminary throughput information early in the design cycle, while the PL developers continue to work on the platform for the application.

Note: Simulating the design with VCD will increase simulation runtime. To learn more about this feature you can read this section here: AI Engine SystemC Simulator.

1. To run simulation you can run the command:

   make sim TARGET=hw
   

   Or

   aiesimulator --profile --dump-vcd=tutorial --pkg-dir=./Work
   

   | Flag | Description | | —- | ———– | | –profile | Profiles All the kernels, or select kernels (col,row)…(col,row).| | –dump-vcd | Grabs internal signals of tiles and dumps it in a VCD file. | | –pkg-dir | The Work directory. |

2. When simulation is completed navigate to the aiesimulator_output directory from a terminal by running: cd aiesimulator_output; ls

   You should see something similar to this:

   aiesim_options.txt      profile_funct_24_0.xml  profile_funct_25_0.xml  profile_instr_24_0.xml  profile_instr_25_0.xml
   data                    profile_funct_24_1.txt  profile_funct_25_1.txt  profile_instr_24_1.txt  profile_instr_25_1.txt  
   default.aierun_summary  profile_funct_24_1.xml  profile_funct_25_1.xml  profile_instr_24_1.xml  profile_instr_25_1.xml
   profile_funct_24_0.txt  profile_funct_25_0.txt  profile_instr_24_0.txt  profile_instr_25_0.txt
   

As you can see a variety of files, the ones prefixed with profile_ are the outputs of the profiling and calculated per tile. In this tutorial, the profiling is done for all tiles that are utilized, but you can limit to specific tiles by providing the row and column of the tile. To see more info about profiling with aiesimulator go here. You can open up these files to see what was calculated, but it is better to view it in Vitis™ Analyzer where it is all curated. The data directory is generated here with the output file(s) you have in the graph.cpp for the PLIO objects. Lastly, the default.aierun_summary is generated, which contains all the information generated by aiesimulator with profiling and trace info, and when opening this file in Vitis Analyzer will allow you to browse all the output files, and profile/trace data.

NOTE: The tutorial.vcd is generated on the same level as the ./Work directory.