Improve wasm calli thunk lookup

[radekdoulik]

Put the thunks into hash table, this will also serve later for the generated thunk lookups

Add CallFunc_F64_RetF64

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Pull Request Overview

This PR refactors the WASM calli thunk lookup system to improve performance and maintainability by replacing array-based lookups with a hash table implementation. It also adds support for new data types in WASM function signatures.

• Replaces direct array indexing with a hash table for thunk lookups to improve performance and scalability
• Adds support for F64 (double) type conversions and a new CallFunc_F64_RetF64 thunk function
• Expands type conversion support to include I8, U8, I64, F32, and F64 element types

[jkotas]

this will also serve later for the generated thunk lookups

Does Mono build the hashtable of the thunks during startup, or is the hashtable pre-built at build time? We may want the latter, especially for AOT.

[radekdoulik]

this will also serve later for the generated thunk lookups

Does Mono build the hashtable of the thunks during startup, or is the hashtable pre-built at build time?

mono currently uses binary search in static table

We may want the latter, especially for AOT.

I think we can improve it gradually? I remember you told me that part of runtime already does something similar, we didn't talk about the details though.

We can use perfect hash or just precompute the hash values for the signature string keys. Or do you have another idea?

[pavelsavara]

runtime already does something similar

This is android for pinvoke by symbol name. They pre-build the hash table.
https://github.com/dotnet/android/blob/main/src/native/clr/pinvoke-override/pinvoke-tables.include

[radekdoulik]

runtime already does something similar

This is android for pinvoke by symbol name. They pre-build the hash table. https://github.com/dotnet/android/blob/main/src/native/clr/pinvoke-override/pinvoke-tables.include

This is sorted table with precalculated keys. I think they use binary search for lookup.

That is similar to what mono does now for interpreter to native.

[radekdoulik]

I think for AOT it would make sense to use actual precalculated hash table, for interp only it will depend on the size, but I don't expect it to be too large.

I think we don't need it now though, that's why I used the existing SHash and runtime initialization.