TVM AOT C+BYOC compilation fails with `expected str but got Object`

[areusch]

Ah no worries, this makes more sense.

@JosseVanDelm

IIUC const auto* pf = runtime::Registry::Get("runtime.CSourceModuleCreate"); gets a PackedFunc for creating (constructing?) a CSourceModule, is there a reason why this has to happen through a PackedFunc?

I think this is mainly convention and a way to avoid #include "../../../../target/source/source_module.h".

@JosseVanDelm

Is there a specific reason why the ARM CMSIS-NN has a separate pass for adding the constants?

These are two different styles of BYOC implementations–DNNL was added earlier than CMSIS-NN, and CMSIS-NN uses a different code-lowering path to take advantage of USMP I believe. DNNL offloads directly from the Relay graph, meaning the compiler doesn’t see any IR that might allow it to e.g. perform memory planning. CMSIS-NN uses the newly-added Relay-to-TIR and TIR-to-Runtime Target hooks. I believe it also modifies constants to adapt them to the format expected by CMSIS-NN.

@JosseVanDelm

BTW, I also tried to call with:

return codegen::CSourceModuleCreate(code, "c", syms, variables);

But this also failed with the same error as above

I don’t think in this case it makes senes to pass variables to CSourceModuleCreate, because it’s not possible to use ConstLoaderModule in the C runtime. In any case, I think that error would be caused by something in variables not being a string.

The ARM CMSIS-NN TIR-to-Runtime hook seems to use the C++ binding. I think that should be fine for you to use (should be equivalent to passing variables as an empty list).