efe3930215
There has been occasional confusion with the representation that we use for bool-typed values in registers, at least when these are wider than one bit. Does a `b8` store `true` as 1, or as all-ones (`0xff`)? We've settled on the latter because of some use-cases where the wide bool becomes a mask -- see #2058 for more on this. This is fine, and transparent, to most operations within CLIF, because the bool-typed value still has only two semantically-visible states, namely `true` and `false`. However, we have to be careful with bool-to-int conversions. `bint` on aarch64 correctly masked the all-ones value down to 0 or 1, as required by the instruction specification, but on x64 it did not. This PR fixes that bug and makes x64 consistent with aarch64. While staring at this code I realized that `bextend` was also not consistent with the all-ones invariant: it should do a sign-extend, not a zero-extend as it previously did. This is also rectified and tested. (Aarch64 also already had this case implemented correctly.) Fixes #3003.
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.
-
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.
-
WASI. Wasmtime supports a rich set of APIs for interacting with the host environment through the WASI standard.
-
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 - [C++] - the
wasmtime-cpprepository - 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.