| This folder is an exmample backend to lower MobileNetV2. It covers the AOT side and showcase how to quantize and lower a MobileNetV2 to the example backend. The serialization format is purely string for demo purpose as it'll be up to backend's decision to choose serialization format. |
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| The folder structure incluces: |
| - example_quantizer |
| - example_partitioner |
| - example_backend |
| - examples_operators. Assuming all of them can run in the example backend. |
| - The OpBase defined in op_base.py is just the draft idea, it can be defined more comprehensively depending example operator definitions |
| - example_backend_delegate_passes. It includes passes that might be helpful in the backend. Right now there are two passes: merge_to_dim_pass.py and permute_memory_formats_pass.py. They are examples to show how to represent memory format permutation and how to represent operators with different memory format (like channel last) |
| - merge_to_dim_pass.py only handles one merging cases. More cases need to be covered but should be straitforward. |
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| ## High Level Flow |
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| In the following diagram, we show how to quantize a mobile net v2 model and lower it to ExampleBackend. |
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| ### Quantize and Delegate |
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| We can define patterns based on the operators supported by the backend, which will be used by the quantizer and delegate. |
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| ### Partitioner and Backend |
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| The way partitioner and backend is, partitioner will tag the nodes to lower to the backend and backend will will receive all tagged nodes and preprocess them as a delegate. |
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| ### Memory format permute |
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| Some operators may have better performance in the memory format other than contiguous. One way to do that is to insert `to_dim_op` to describe memory format permutation and merge if there two opposite one next to each other. |
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