AddingExecutionProvider.md

Adding a new execution provider

• Create a folder under onnxruntime/core/providers
• Create a folder under include/onnxruntime/core/providers, it should has the same name as the first step.
• Create a new class, which must inherit from IExecutionProvider. The source code should be put in 'onnxruntime/core/providers/[your_provider_name]'
• Create a new header file under include/onnxruntime/core/providers/[your_provider_name]. The file should provide one function for creating an OrtProviderFactoryInterface. You may use 'include/onnxruntime/core/providers/cpu/cpu_provider_factory.h' as a template. You don't need to provide a function for creating AllocatorInfo.
• Put a symbols.txt under 'onnxruntime/core/providers/[your_provider_name]'. The file should contain all the function names that would be exported from you provider. Usually, just a single function for creating provider factory is enough.
• Add your provider in onnxruntime_providers.cmake. Build it as a static lib.
• Add one line in cmake/onnxruntime.cmake, to the 'target_link_libraries' function call. Put your provider there.

Examples:

• CPU Execution Provider
• CUDA Execution Provider
• MKL-DNN Execution Provider

Using the execution provider

1. Create a factory for that provider, by using the c function you exported in 'symbols.txt'
2. Put the provider factory into session options
3. Create session from that session option e.g.

  OrtEnv* env;
  OrtInitialize(ORT_LOGGING_LEVEL_WARNING, "test", &env)
  OrtSessionOptions* session_option = OrtCreateSessionOptions();
  OrtProviderFactoryInterface** factory;
  OrtCreateCUDAExecutionProviderFactory(0, &factory);
  OrtSessionOptionsAppendExecutionProvider(session_option, factory);
  OrtReleaseObject(factory);
  OrtCreateSession(env, model_path, session_option, &session);