Vitis Model Composer Hub Block for Verification - 2025.2 English - UG1483

Vitis Model Composer User Guide (UG1483)
Document ID
UG1483
Release Date
2025-11-20
Version
2025.2 English

To verify and analyze the AI Engine design, use the Analyze tab of the Model Composer Hub block.

Figure 1. Vitis Model Composer Hub: Testbench and Simulator Options

The Analyze button generates and compiles AI Engine code from the design and run the cycle-approximate AIE Simulation (SystemC).

The Simulation timeout value limits the execution to the specified number of cycles. This is necessary because of the finite amount of input data. If you do not specify the timeout value, the AI Engine kernels are invoked repeatedly forever (that is, the graph runs infinitely). To avoid this situation, specify the Simulation timeout value as shown in the preceding figure.

The default timeout value is 50,000 cycles. The tool uses this value to terminate the simulation after the specified number of clock cycles.

AI Engine code verification and analysis advances in three phases:

  1. Compiling the AI Engine graph design.
  2. Running simulation using the AI Engine simulator.
  3. Verifying the simulation results by comparing the output with the golden reference output.

After clicking Analyze, you can monitor the compilation, simulation, and verification progress of the AI Engine graph code from the Progress window. See the following figure.

Figure 2. Graph Code Progress

After successful compilation and simulation, Model Composer automatically compares the target output with the golden reference output. It returns the following message in the Progress window (or in the corresponding simulation log files).

Comparing simulation results ...
Output data file : data/aiesimulator_output/Outl.txt.mod
reference data file : data/reference_output/Outl.txt
Simulation results MATCH.
**********************************************************
Test PASSED
Verification Complete
Note: In some scenarios, the simulator output produces fewer samples when compared with the golden output or vice-versa. In such cases, the test result still show as 'PASS.' This indicates that the first 'n' lines from the simulation output matches the first 'n' lines of the golden output and the results partially match. The .diff file in the corresponding simulator output captures any difference with the reference output.

In addition to this, the AI Engine compiler writes various configuration and binary files to the work/aie directory. For more information on the structure and contents of the directory specific to the compilation, see the AI Engine Tools and Flows User Guide (UG1076).