How to implement relay to onnx codegen in C++

Relay to onnx codegen has implemented in python just like /python/tvm/contrib/target/onnx.py. But in our online scenario python is unused. How to implement relay to onnx codegen in c++?

Is there a tool / API that convert relay to onnx? I think we can only convert onnx to relay but not vice versa.

Yes. /python/tvm/contrib/target/onnx.py can relay to onnx with python. But I want to relay to onnx with C++…