9ac7d01288
This commit is intended to do almost everything necessary for processing the alias section of module linking. Most of this is internal refactoring, the highlights being: * Type contents are now stored separately from a `wasmtime_env::Module`. Given that modules can freely alias types and have them used all over the place, it seemed best to have one canonical location to type storage which everywhere else points to (with indices). A new `TypeTables` structure is produced during compilation which is shared amongst all member modules in a wasm blob. * Instantiation is heavily refactored to account for module linking. The main gotcha here is that imports are now listed as "initializers". We have a sort of pseudo-bytecode-interpreter which interprets the initialization of a module. This is more complicated than just matching imports at this point because in the module linking proposal the module, alias, import, and instance sections may all be interleaved. This means that imports aren't guaranteed to show up at the beginning of the address space for modules/instances. Otherwise most of the changes here largely fell out from these two design points. Aliases are recorded as initializers in this scheme. Copying around type information and/or just knowing type information during compilation is also pretty easy since everything is just a pointer into a `TypeTables` and we don't have to actually copy any types themselves. Lots of various refactorings were necessary to accomodate these changes. Tests are hoped to cover a breadth of functionality here, but not necessarily a depth. There's still one more piece of the module linking proposal missing which is exporting instances/modules, which will come in a future PR. It's also worth nothing that there's one large TODO which isn't implemented in this change that I plan on opening an issue for. With module linking when a set of modules comes back from compilation each modules has all the trampolines for the entire set of modules. This is quite a lot of duplicate trampolines across module-linking modules. We'll want to refactor this at some point to instead have only one set of trampolines per set of module linking modules and have them shared from there. I figured it was best to separate out this change, however, since it's purely related to resource usage, and doesn't impact non-module-linking modules at all. cc #2094
wasmtime
A standalone runtime for WebAssembly
A Bytecode Alliance project
Guide | Contributing | Website | Chat
Installation
The Wasmtime CLI can be installed on Linux and macOS with a small install script:
$ curl https://wasmtime.dev/install.sh -sSf | bash
Windows or otherwise interested users can download installers and binaries directly from the GitHub Releases page.
Example
If you've got the Rust compiler installed then you can take some Rust source code:
fn main() {
println!("Hello, world!");
}
and compile/run it with:
$ rustup target add wasm32-wasi
$ rustc hello.rs --target wasm32-wasi
$ wasmtime hello.wasm
Hello, world!
Features
-
Lightweight. Wasmtime is a standalone runtime for WebAssembly that scales with your needs. It fits on tiny chips as well as makes use of huge servers. Wasmtime can be embedded into almost any application too.
-
Fast. Wasmtime is built on the optimizing Cranelift code generator to quickly generate high-quality machine code at runtime.
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Configurable. Whether you need to precompile your wasm ahead of time, generate code blazingly fast with Lightbeam, or interpret it at runtime, Wasmtime has you covered for all your wasm-executing needs.
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WASI. Wasmtime supports a rich set of APIs for interacting with the host environment through the WASI standard.
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Standards Compliant. Wasmtime passes the official WebAssembly test suite, implements the official C API of wasm, and implements future proposals to WebAssembly as well. Wasmtime developers are intimately engaged with the WebAssembly standards process all along the way too.
Language Support
You can use Wasmtime from a variety of different languages through embeddings of the implementation:
- Rust - the
wasmtimecrate - C - the
wasm.h,wasi.h, andwasmtime.hheaders - Python - the
wasmtimePyPI package - .NET - the
WasmtimeNuGet package - Go - the
wasmtime-gorepository
Documentation
📚 Read the Wasmtime guide here! 📚
The wasmtime guide is the best starting point to learn about what Wasmtime can do for you or help answer your questions about Wasmtime. If you're curious in contributing to Wasmtime, it can also help you do that!.
It's Wasmtime.