5d671952ee
This PR fixes #4066: it modifies the Cranelift `build.rs` workflow to invoke the ISLE DSL compiler on every compilation, rather than only when the user specifies a special "rebuild ISLE" feature. The main benefit of this change is that it vastly simplifies the mental model required of developers, and removes a bunch of failure modes we have tried to work around in other ways. There is now just one "source of truth", the ISLE source itself, in the repository, and so there is no need to understand a special "rebuild" step and how to handle merge errors. There is no special process needed to develop the compiler when modifying the DSL. And there is no "noise" in the git history produced by constantly-regenerated files. The two main downsides we discussed in #4066 are: - Compile time could increase, by adding more to the "meta" step before the main build; - It becomes less obvious where the source definitions are (everything becomes more "magic"), which makes exploration and debugging harder. This PR addresses each of these concerns: 1. To maintain reasonable compile time, it includes work to cut down the dependencies of the `cranelift-isle` crate to *nothing* (only the Rust stdlib), in the default build. It does this by putting the error-reporting bits (`miette` crate) under an optional feature, and the logging (`log` crate) under a feature-controlled macro, and manually writing an `Error` impl rather than using `thiserror`. This completely avoids proc macros and the `syn` build slowness. The user can still get nice errors out of `miette`: this is enabled by specifying a Cargo feature `--features isle-errors`. 2. To allow the user to optionally inspect the generated source, which nominally lives in a hard-to-find path inside `target/` now, this PR adds a feature `isle-in-source-tree` that, as implied by the name, moves the target for ISLE generated source into the source tree, at `cranelift/codegen/isle_generated_source/`. It seems reasonable to do this when an explicit feature (opt-in) is specified because this is how ISLE regeneration currently works as well. To prevent surprises, if the feature is *not* specified, the build fails if this directory exists.
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, 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 or usewasmtimeConan package - C++ - the
wasmtime-cpprepository or usewasmtime-cppConan package - 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.