How to remove no-op exported functions? about binaryen HOT 3 OPEN

Two possible ways to add such a feature:

1. As a pass-option for RemoveUnusedModuleElements pass.
2. Add a flag to wasm-metadce.
   In both cases the option would be something like "consider empty exports unused".

Which runtime is this, btw, that will safely ignore empty exports?

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I see, thanks for the info @orsinium !

With multiple VMs that could benefit here, this sounds very reasonable to add as an option.

Probably the first option I mentioned before (pass-option for RemoveUnusedModuleElements) is best. If someone has time to look into that but doesn't know where to start I can help out with guidance.

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Which runtime is this, btw, that will safely ignore empty exports?

I'm building my own Rust runtime on top of wasmi. Knowing that the guest does not implement certain functions lets me do host-side optimizations. Similar to how pico-8 changes the frame rate to 60 FPS if _UPDATE60 function is provided.

Another example is wasm-4. It expects start and update exports both of which may be omitted:

• https://github.com/aduros/wasm4/blob/main/runtimes/web/src/runtime.ts#L319-L322
• https://github.com/aduros/wasm4/blob/main/runtimes/web/src/runtime.ts#L334-L338

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