... and add a parallel raytracing demo!
This commit adds enough support to `wasm-bindgen` to produce a workable
wasm binary *today* with the experimental WebAssembly threads support
implemented in Firefox Nightly. I've tried to comment what's going on in
the commits and such, but at a high level the changes made here are:
* A new transformation, living in a new `wasm-bindgen-threads-xform`
crate, prepares a wasm module for parallel execution. This performs a
number of mundane tasks which I hope to detail in a blog post later on.
* The `--no-modules` output is enhanced with more support for when
shared memory is enabled, allowing passing in the module/memory to
initialize the wasm instance on multiple threads (sharing both module
and memory).
* The `wasm-bindgen` crate now offers the ability, in `--no-modules`
mode, to get a handle on the `WebAssembly.Module` instance.
* The example itself requires Xargo to recompile the standard library
with atomics and an experimental feature enabled. Afterwards it
experimentally also enables threading support in wasm-bindgen.
I've also added hopefully enough CI support to compile this example in a
builder so we can upload it and poke around live online. I hope to
detail more about the technical details here in a blog post soon as
well!
I've noticed this in a few cases where it's sometimes easy to have a
`WebAssembly.Module` on-hand for the `--no-modules` mode where you don't
want to necessarily `fetch`. This commit changes the exported
initialization function in `--no-modules` mode to support both!
This commit migrates away from using Serde for the custom section in
wasm executables. This is a refactoring of a purely-internal data
structure to `wasm-bindgen` and should have no visible functional change
on users.
The motivation for this commit is two fold:
* First, the compile times using `serde_json` and `serde_derive` for the
syntax extension isn't the most fun.
* Second, eventually we're going to want to stablize the layout of the
custom section, and it's highly unlikely to be json!
Primarily, though, the intention of this commit is to improve the
cold-cache compile time of `wasm-bindgen` by ensuring that for new users
this project builds as quickly as possible. By removing some heavyweight
dependencies from the procedural macro, `serde`, `serde_derive`, and
`serde_json`, we're able to get a pretty nice build time improvement for
the `wasm-bindgen` crate itself:
| | single-core build | parallel build |
|-------------|-------------------|----------------|
| master | 36.5s | 17.3s |
| this commit | 20.5s | 11.8s |
These are't really end-all-be-all wins but they're much better
especially on the spectrum of weaker CPUs (in theory modeled by the
single-core case showing we have 42% less CPU work in theory).
This commit fixes instantiation of the wasm module even if some of the
improted APIs don't exist. This extends the functionality initially
added in #409 to attempt to gracefully allow importing values from the
environment which don't actually exist in all contexts. In addition to
nonexistent methods being handled now entire nonexistent types are now
also handled.
I suspect that eventually we'll add a CLI flag to `wasm-bindgen` to say
"I assert everything exists, don't check it" to trim out the extra JS
glue generated here. In the meantime though this'll pave the way for a
wasm-bindgen shim to be instantiated in both a web worker and the main
thread, while using DOM-like APIs only on the main thread.
The bindings generation for a class would accidentally omit the `__wrap`
function if it was only discovered very late in the process that
`__wrap` was needed, after we'd already passed the point where we needed
to have decided that.
This commit moves struct field generation of bindings much earlier in
the binding generation process which should ensure everything is all
hooked up by the time we generate the classes themselves.
Closes#949
The `wasm-bindgen` crate is effectively the only user of this crate now
that the `wasm-gc` tool has been deprecated. It's also much easier to
keep it in this repository as it's easier to sync changes to
`parity-wasm`. I'd also like to start refactoring out utilities for
managing a `parity_wasm::Module` to share between this crate and the
other CLI support code.
This commit does a few things, including:
* Fixing the generated JS of `wasm-bindgen` to allow polyfills to work.
(a minor tweak of the generated JS)
* All examples are updated to include a Webpack-specific polyfill for
these two types to get examples working in Edge.
* A new page has been added to the guide about supported browsers. This
mentions known caveats like IE 11 requiring `wasm2js` as well as
documenting some `TextEncoder` and `TextDecoder` workarounds for Edge.
Closes#895
This commit improves the codegen for `Closure<T>`, primarily for ZST
where the closure doesn't actually capture anything. Previously
`wasm-bindgen` would unconditionally allocate an `Rc` for a fat pointer,
meaning that it would always hit the allocator even when the `Box<T>`
didn't actually contain an allocation. Now the reference count for the
closure is stored on the JS object rather than in Rust.
Some more advanced tests were added along the way to ensure that
functionality didn't regress, and otherwise the calling convention for
`Closure` changed a good deal but should still be the same user-facing.
The primary change was that the reference count reaching zero may cause
JS to need to run the destructor. It simply returns this information in
`Drop for Closure` and otherwise when calling it now also retains a
function pointer that runs the destructor.
Closes#874
This commit implements support for binding APIs that take
`Uint8ClampedArray` in JS. This is pretty rare but comes up in a
`web-sys` binding or two, and we're now able to bind these APIs instead
of having to omit the bindings.
The `Uint8ClampedArray` type is bound by using the `Clamped` marker
struct in Rust. For example this is declaring a JS API that takes
`Uint8ClampedArray`:
use wasm_bindgen::Clamped;
#[wasm_bindgen]
extern {
fn takes_clamped(a: Clamped<&[u8]>);
}
The `Clamped` type currently only works when wrapping the `&[u8]`, `&mut
[u8]`, and `Vec<u8>` types. Everything else will produce an error at
`wasm-bindgen` time.
Closes#421
All these functions are now provided by upstream compiler-builtins, so
there's no need for us to be binding them automatically. The remaining
`Math_*` functions are also no longer needed on nightly after
https://github.com/rust-lang/rust/pull/54257 but that PR isn't on beta,
so we'll need to leave these here for awhile while beta rides the trains
This commit removes the need for an injected `ConstructorToken` type and
also cleans up the story we have for generating constructors a bit.
After this commit a `constructor()` is omitted entirely if we're in
non-debug mode and there's no actual listed constructor. Additionally we
don't deal with splat arguments and rerouting constructors, Nick was
kind enough to enlighten me about `Object.create` which is creating an
instance without running the constructor!
Instances of an exported type are now created through one of two
methods:
* If `#[wasm_bindgen(constructor)]` is present, then a `constructor` is
generated with the appropriate signature. If a constructor is not
present and we're in debug mode, a throwing constructor is generated.
If we're in release mode and there's no constructor, no constructor is
generated.
* Otherwise if a binding returns an instance of a type (or otherwise
needs to manfuacture an instance, then it will cause an internal
`__wrap` function to be generated. This function will use
`Object.create` to create an instance without running the constructor.
This should ideally clean up our generated JS for classes quite a bit,
making it much more lean-and-mean!
Previously `wasm-bindgen` would take its `breaks_if_inlined` shims and
attempt to remove them entirely, replacing calls to `breaks_if_inlined`
to the imported closure factories. This worked great in that it would
remove the `breaks_if_inlined` funtion entirely, removing the "cost" of
the `#[inline(never)]`.
Unfortunately as #864 discovered this is "too clever by half". LLVM's
aggressive optimizations won't inline `breaks_if_inlined`, but it may
still change the ABI! We can't replace calls to `breaks_if_inlined` if
the signature changes, because the function its calling has a fixed signature.
This commit cops out a bit and instead of replacing calls to
`breaks_if_inlined` to the imported closure factories, we instead
rewrite calls to `__wbindgen_describe_closure` to the closure factories.
This means that the `breaks_if_inlined` shims do not get removed. It
also means that the closure factory shims have a third and final
argument (what would be the function pointer of the descriptor function)
which is dead and unused.
This should be a functional solution for now and let us iterate on a
true fix later on (if needed). For now the cost of this
`#[inline(never)]` and the extra unused argument should be quite small.
Closes#864
This commit adds support for exporting a function defined in Rust that returns a
`Result`, translating the `Ok` variant to the actual return value and the `Err`
variant to an exception that's thrown in JS.
The support for return types and descriptors was rejiggered a bit to be a bit
more abstract and more well suited for this purpose. We no longer distinguish
between functions with a return value and those without a return value.
Additionally a new trait, `ReturnWasmAbi`, is used for converting return values.
This trait is an internal implementation detail, however, and shouldn't surface
itself to users much (if at all).
Closes#841
This is intended to address #834 where we don't actually want methods scoped
like this! Instead we'll provide one unique accessor for the `window` object
itself.
This resulted in trailing whitespace in the generated file. In addition
to wasting space in a file that gets served over the wire, this also
gets highlighted as a problem when reviewing the generated file in an
editor that highlights trailing whitespace.
The output using modules already uses string formatting that carefully
avoids emitting leading and trailing blanks; adjust the --no-modules
output to match.
This commit adds an implementation of `AsRef<JsValue>` for the `Closure<T>`
type. Previously this was not possible because the `JsValue` didn't actually
exist until the closure was passed to JS, but the implementation has been
changed to ... something a bit more unconventional. The end result, however, is
that `Closure<T>` now always contains a `JsValue`.
The end result of this work is intended to be a precursor to binding callbacks
in `web-sys` as `JsValue` everywhere but still allowing usage with `Closure<T>`.
This commit adds further support for the `Global` attribute to not only emit
structural accessors but also emit functions that don't take `&self`. All
methods on a `[Global]` interface will not require `&self` and will call
functions and/or access properties on the global scope.
This should enable things like:
Window::location() // returns `Location`
Window::fetch(...) // invokes the `fetch` function
Closes#659
We currently pass a raw view into wasm's memory for `getStringFromWasm`, but if
the memory is actually shared then `TextDecoder` rejects `SharedArrayBuffer` and
won't actually decode anything. Work around this for now with an extra copy into
a local buffer, and then pass that buffer to `getStringFromWasm` whenever memory
is shared.