feat(vm): escaped functions cap during preparation#16050
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The VM currently has not explicit limit on declared Wasm globals in a contract. However, `MAX_CORE_INSTANCE_SIZE = 1MiB` acts as an implicit limit today. This PR sets the limit to 100k global, which would add 1.6MB to the core instance size, thus is less restrictive than the existing limit. A follow-up PR will make this limit stricter and combine it with other limits that contribute to MAX_CORE_INSTANCE_SIZE. But the goal is to introduce each limit in a separate PR before combining them.
Wasmtime limits the core instance size, whose size increases with the number of escaped functions. To avoid running into it at load time, this introduces a limit at preparation time. This requires counting escaped functions in the preparation phase and if that breaches the configured limit, a new error kind is retured as a CompilationError::PrepareError. Gated behind the unstable nightly version 157 for stabilization together with all other limits regarding the core instance size.
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Wasmtime limits the core instance size, whose size increases with the
number of escaped functions.
To avoid running into it at load time, this introduces a limit at
preparation time. This requires counting escaped functions in the
preparation phase and if that breaches the configured limit, a new error
kind is retured as a CompilationError::PrepareError.
Gated behind the unstable nightly version 157 for stabilization together
with all other limits regarding the core instance size.