* Remove unnecessary into_iter/map Forgotten from a previous refactoring, this variable was already of the right type! * Move `wasmtime_jit::Compiler` into `wasmtime` This `Compiler` struct is mostly a historical artifact at this point and wasn't necessarily pulling much weight any more. This organization also doesn't lend itself super well to compiling out `cranelift` when the `Compiler` here is used for both parallel iteration configuration settings as well as compilation. The movement into `wasmtime` is relatively small, with `Module::build_artifacts` being the main function added here which is a merging of the previous functions removed from the `wasmtime-jit` crate. * Add a `cranelift` compile-time feature to `wasmtime` This commit concludes the saga of refactoring Wasmtime and making Cranelift an optional dependency by adding a new Cargo feature to the `wasmtime` crate called `cranelift`, which is enabled by default. This feature is implemented by having a new cfg for `wasmtime` itself, `cfg(compiler)`, which is used wherever compilation is necessary. This bubbles up to disable APIs such as `Module::new`, `Func::new`, `Engine::precompile_module`, and a number of `Config` methods affecting compiler configuration. Checks are added to CI that when built in this mode Wasmtime continues to successfully build. It's hoped that although this is effectively "sprinkle `#[cfg]` until things compile" this won't be too too bad to maintain over time since it's also an use case we're interested in supporting. With `cranelift` disabled the only way to create a `Module` is with the `Module::deserialize` method, which requires some form of precompiled artifact. Two consequences of this change are: * `Module::serialize` is also disabled in this mode. The reason for this is that serialized modules contain ISA/shared flags encoded in them which were used to produce the compiled code. There's no storage for this if compilation is disabled. This could probably be re-enabled in the future if necessary, but it may not end up being all that necessary. * Deserialized modules are not checked to ensure that their ISA/shared flags are compatible with the host CPU. This is actually already the case, though, with normal modules. We'll likely want to fix this in the future using a shared implementation for both these locations. Documentation should be updated to indicate that `cranelift` can be disabled, although it's not really the most prominent documentation because this is expected to be a somewhat niche use case (albeit important, just not too common). * Always enable cranelift for the C API * Fix doc example builds * Fix check tests on GitHub Actions
Wasmtime Embedding API
The wasmtime crate is an embedding API of the wasmtime WebAssembly runtime.
This is intended to be used in Rust projects and provides a high-level API of
working with WebAssembly modules.
If you're interested in embedding wasmtime in other languages, you may wish to
take a look a the C embedding API instead!