Cursed implementation of allowing missing imports on wasmtime #4730
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bkchr
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bkchr
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Looks good so far, just some small improvements :)
| func_ty | ||
| } | ||
| _ => { | ||
| // The executor doesn't provide any non function imports! |
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When we switch to import memory, will this not "break" here? Why not ignore non function imports?
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Yeah, it will bail here! We can remove this in rely it to fail at the instantiation time.
| }; | ||
| let signature = convert_parity_wasm_signature(func_ty); | ||
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| if import_entry.module() == "env" { |
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Can we have function exports that don't have the module env?
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Yeah, we can! If I remember correctly, in Rust you'd use #[link(wasm_import_module = "non_env")] for that.
| MissingFunctionStubs::new() | ||
| }; | ||
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| let env_missing_functions = missing_functions_stubs.stubs.remove("env").unwrap_or_else(|| Vec::new()); |
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Can we not do this in the loop below and just check:
if module == env {
host_functions
} else {
&[]
}
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The main point of doing that is not in host functions but rather in creating a new instance and giving it a name for non-env modules.
Co-Authored-By: Bastian Köcher <[email protected]>
This is a quick and dirty implementation of the wasmtime counterpart of #4550. This is aimed to unblock polkadot progress while we are waiting #4686.
The idea is that we employ parity-wasm to extract all the imports and do the resolving ourselves, then we collect all the missing function imports and create modules and stubs for them.