* Cranelift: Deduplicate ABI signatures during lowering This commit creates the `SigSet` type which interns and deduplicates the ABI signatures that we create from `ir::Signature`s. The ABI signatures are now referred to indirectly via a `Sig` (which is a `cranelift_entity` ID), and we pass around a `SigSet` to anything that needs to access the actual underlying `SigData` (which is what `ABISig` used to be). I had to change a couple methods to return a `SmallInstVec` instead of emitting directly to work around what would otherwise be shared and exclusive borrows of the lowering context overlapping. I don't expect any of these to heap allocate in practice. This does not remove the often-unnecessary allocations caused by `ensure_struct_return_ptr_is_returned`. That is left for follow up work. This also opens the door for further shuffling of signature data into more efficient representations in the future, now that we have `SigSet` to store it all in one place and it is threaded through all the code. We could potentially move each signature's parameter and return vectors into one big vector shared between all signatures, for example, which could cut down on allocations and shrink the size of `SigData` since those `SmallVec`s have pretty large inline capacity. Overall, this refactoring gives a 1-7% speedup for compilation on `pulldown-cmark`: ``` compilation :: cycles :: benchmarks/pulldown-cmark/benchmark.wasm Δ = 8754213.66 ± 7526266.23 (confidence = 99%) dedupe.so is 1.01x to 1.07x faster than main.so! [191003295 234620642.20 280597986] dedupe.so [197626699 243374855.86 321816763] main.so compilation :: cycles :: benchmarks/bz2/benchmark.wasm No difference in performance. [170406200 194299792.68 253001201] dedupe.so [172071888 193230743.11 223608329] main.so compilation :: cycles :: benchmarks/spidermonkey/benchmark.wasm No difference in performance. [3870997347 4437735062.59 5216007266] dedupe.so [4019924063 4424595349.24 4965088931] main.so ``` * Use full path instead of import to avoid warnings in some build configurations Warnings will then cause CI to fail. * Move `SigSet` into `VCode`
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
-
Fast. Wasmtime is built on the optimizing Cranelift code generator to quickly generate high-quality machine code either at runtime or ahead-of-time. Wasmtime is optimized for efficient instantiation, low-overhead calls between the embedder and wasm, and scalability of concurrent instances.
-
Secure. Wasmtime's development is strongly focused on correctness and security. Building on top of Rust's runtime safety guarantees, each Wasmtime feature goes through careful review and consideration via an RFC process. Once features are designed and implemented, they undergo 24/7 fuzzing donated by Google's OSS Fuzz. As features stabilize they become part of a release, and when things go wrong we have a well-defined security policy in place to quickly mitigate and patch any issues. We follow best practices for defense-in-depth and integrate protections and mitigations for issues like Spectre. Finally, we're working to push the state-of-the-art by collaborating with academic researchers to formally verify critical parts of Wasmtime and Cranelift.
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Configurable. Wasmtime uses sensible defaults, but can also be configured to provide more fine-grained control over things like CPU and memory consumption. Whether you want to run Wasmtime in a tiny environment or on massive servers with many concurrent instances, we've got you covered.
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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, CMake orwasmtimeConan 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.