* Fix some nightly dead code warnings
Looks like the "struct field not used" lint has improved on nightly and
caught a few more instances of fields that were never actually read.
* Fix windows
This commit removes the `differential_spec` fuzz target for now,
although this removal is intended to be temporary. We have #3251 to
track re-enabling the spec interpreter in a way that it won't time out,
and additionally the spec interpreter is also failing to build with
ocaml on oss-fuzz so that will also need to be investigated when
re-enabling.
* Support full set of ADD LOGICAL / SUBTRACT LOGICAL instructions
* Full implementation of IaddIfcout lowering
* Enable most memory64 tests (except simd and threads)
We already validate wasm functions in parallel when compiling a module,
but the same parallelism wasn't available to the `Module::validate` API.
This commit peforms a minor tweak to the validate-the-whole-module API
to validate all functions in parallel in the same manner that module
compilation does.
Revert the part of 47490b4383 which
changed cranelift-native to use rsix. It's just one call, and this lets
Cranelift users that don't otherwise depend on rsix to avoid it.
This commit removes the Lightbeam backend from Wasmtime as per [RFC 14].
This backend hasn't received maintenance in quite some time, and as [RFC
14] indicates this doesn't meet the threshold for keeping the code
in-tree, so this commit removes it.
A fast "baseline" compiler may still be added in the future. The
addition of such a backend should be in line with [RFC 14], though, with
the principles we now have for stable releases of Wasmtime. I'll close
out Lightbeam-related issues once this is merged.
[RFC 14]: https://github.com/bytecodealliance/rfcs/pull/14
* Add `*_unchecked` variants of `Func` APIs for the C API
This commit is what is hopefully going to be my last installment within
the saga of optimizing function calls in/out of WebAssembly modules in
the C API. This is yet another alternative approach to #3345 (sorry) but
also contains everything necessary to make the C API fast. As in #3345
the general idea is just moving checks out of the call path in the same
style of `TypedFunc`.
This new strategy takes inspiration from previously learned attempts
effectively "just" exposes how we previously passed `*mut u128` through
trampolines for arguments/results. This storage format is formalized
through a new `ValRaw` union that is exposed from the `wasmtime` crate.
By doing this it made it relatively easy to expose two new APIs:
* `Func::new_unchecked`
* `Func::call_unchecked`
These are the same as their checked equivalents except that they're
`unsafe` and they work with `*mut ValRaw` rather than safe slices of
`Val`. Working with these eschews type checks and such and requires
callers/embedders to do the right thing.
These two new functions are then exposed via the C API with new
functions, enabling C to have a fast-path of calling/defining functions.
This fast path is akin to `Func::wrap` in Rust, although that API can't
be built in C due to C not having generics in the same way that Rust
has.
For some benchmarks, the benchmarks here are:
* `nop` - Call a wasm function from the host that does nothing and
returns nothing.
* `i64` - Call a wasm function from the host, the wasm function calls a
host function, and the host function returns an `i64` all the way out to
the original caller.
* `many` - Call a wasm function from the host, the wasm calls
host function with 5 `i32` parameters, and then an `i64` result is
returned back to the original host
* `i64` host - just the overhead of the wasm calling the host, so the
wasm calls the host function in a loop.
* `many` host - same as `i64` host, but calling the `many` host function.
All numbers in this table are in nanoseconds, and this is just one
measurement as well so there's bound to be some variation in the precise
numbers here.
| Name | Rust | C (before) | C (after) |
|-----------|------|------------|-----------|
| nop | 19 | 112 | 25 |
| i64 | 22 | 207 | 32 |
| many | 27 | 189 | 34 |
| i64 host | 2 | 38 | 5 |
| many host | 7 | 75 | 8 |
The main conclusion here is that the C API is significantly faster than
before when using the `*_unchecked` variants of APIs. The Rust
implementation is still the ceiling (or floor I guess?) for performance
The main reason that C is slower than Rust is that a little bit more has
to travel through memory where on the Rust side of things we can
monomorphize and inline a bit more to get rid of that. Overall though
the costs are way way down from where they were originally and I don't
plan on doing a whole lot more myself at this time. There's various
things we theoretically could do I've considered but implementation-wise
I think they'll be much more weighty.
* Tweak `wasmtime_externref_t` API comments
If Wasmtime thinks a module stack-overflows and v8 says that it does
something else that's ok. This means that the limits on v8 and Wasmtime
are different which is expected and not something we want fuzz-bugs
about.
The LICENSE file is missing in wasmtime-types crate.
As per the Apache 2.0 license, the license file itself
should be redistributed with the source code.
