40db4de44a
If an instruction has more than one trap record associated with it (for example: a divide instruction that has participated in load-op fusion, so we have both a heap-out-of-bounds trap record due to its load and a divide-by-zero trap record due to its divide op), the current MachBuffer code would emit only one of the trap records to the sink. Separately, divide instructions probably shouldn't merge loads, because the two separate possible traps at one location might be confusing for some embedders (certainly in Lucet). Divide seems to be the only case in our current codegen where such merging might occur. This PR changes the lowering to always force the divisor into a register. Finally, while working out why trap records were not appearing, I had noticed that `isa::x64::emit_std_enc_mem()` was only emitting heap-OOB trap metadata for loads/stores when it had a srcloc. This PR ensures that the metadata is emitted even when the srcloc is empty. Note that none of the above presents a security or correctness problem; trap metadata only affects the status that we return to the embedder when a Wasm program terminates with a trap.
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.