4dce51096d
In existing MachInst backends, many instructions -- any that can trap or result in a relocation -- carry `SourceLoc` values in order to propagate the location-in-original-source to use to describe resulting traps or relocation errors. This is quite tedious, and also error-prone: it is likely that the necessary plumbing will be missed in some cases, and in any case, it's unnecessarily verbose. This PR factors out the `SourceLoc` handling so that it is tracked during emission as part of the `EmitState`, and plumbed through automatically by the machine-independent framework. Instruction emission code that directly emits trap or relocation records can query the current location as necessary. Then we only need to ensure that memory references and trap instructions, at their (one) emission point rather than their (many) lowering/generation points, are wired up correctly. This does have the side-effect that some loads and stores that do not correspond directly to user code's heap accesses will have unnecessary but harmless trap metadata. For example, the load that fetches a code offset from a jump table will have a 'heap out of bounds' trap record attached to it; but because it is bounds-checked, and will never actually trap if the lowering is correct, this should be harmless. The simplicity improvement here seemed more worthwhile to me than plumbing through a "corresponds to user-level load/store" bit, because the latter is a bit complex when we allow for op merging. Closes #2290: though it does not implement a full "metadata" scheme as described in that issue, this seems simpler overall.
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 - 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.