b97f07b405
This PR makes use of the support in #2366 for sinking effectful instructions and merging them with consumers. In particular, on x86, we want to make use of the ability of many instructions to load one operand directly from memory. That is, instead of this: ``` movq 0(%rdi), %rax addq %rax, %rbx ``` we want to generate this: ``` addq 0(%rdi), %rax ``` As described in more detail in #2366, sinking and merging the load is only possible under certain conditions. In particular, we need to ensure that the use is the *only* use (otherwise the load happens more than once), and we need to ensure that it does not move across other effectful ops (see #2366 for how we ensure this). This change is actually fairly simple, given that all the framework is in place: we simply pattern-match a load on one operand of an ALU instruction that takes an RMI (reg, mem, or immediate) operand, and generate the mem form when we match. Also makes a drive-by improvement in the x64 backend to use statically-monomorphized `LowerCtx` types rather than a `&mut dyn LowerCtx`. On `bz2.wasm`, this results in ~1% instruction-count reduction. More is likely possible by following up with other instructions that can merge memory loads as well.
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.
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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.