uextend/sextend to ISLE
This commit migrates the sign/zero extension instructions from
`lower_inst.rs` to ISLE. There's actually a fair amount going on in this
migration since a few other pieces needed touching up along the way as
well:
* First is the actual migration of `uextend` and `sextend`. These
instructions are relatively simple but end up having a number of special
cases. I've attempted to replicate all the cases here but
double-checks would be good.
* This commit actually fixes a few issues where if the result of a vector
extraction is sign/zero-extended into i128 that actually results in
panics in the current backend.
* This commit adds exhaustive testing for
extension-of-a-vector-extraction is a noop wrt extraction.
* A bugfix around ISLE glue was required to get this commit working,
notably the case where the `RegMapper` implementation was trying to
map an input to an output (meaning ISLE was passing through an input
unmodified to the output) wasn't working. This requires a `mov`
instruction to be generated and this commit updates the glue to do
this. At the same time this commit updates the ISLE glue to share more
infrastructure between x64 and aarch64 so both backends get this fix
instead of just aarch64.
Overall I think that the translation to ISLE was a net benefit for these
instructions. It's relatively obvious what all the cases are now unlike
before where it took a few reads of the code and some boolean switches
to figure out which path was taken for each flavor of input. I think
there's still possible improvements here where, for example, the
`put_in_reg_{s,z}ext64` helper doesn't use this logic so technically
those helpers could also pattern match the "well atomic loads and vector
extractions automatically do this for us" but that's a possible future
improvement for later (and shouldn't be too too hard with some ISLE
refactoring).
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.