* Add a first-class way of accessing caller's exports
This commit is a continuation of #1237 and updates the API of `Func` to
allow defining host functions which have easy access to a caller's
memory in particular. The new APIs look like so:
* The `Func::wrap*` family of functions was condensed into one
`Func::wrap` function.
* The ABI layer of conversions in `WasmTy` were removed
* An optional `Caller<'_>` argument can be at the front of all
host-defined functions now.
The old way the wasi bindings looked up memory has been removed and is
now replaced with the `Caller` type. The `Caller` type has a
`get_export` method on it which allows looking up a caller's export by
name, allowing you to get access to the caller's memory easily, and even
during instantiation.
* Add a temporary note
* Move some docs
* Add API to statically assert signature of a `Func`
This commit add a family of APIs to `Func` named `getN` where `N` is the
number of arguments. Each function will attempt to statically assert the
signature of a `Func` and, if matching, returns a corresponding closure
which can be used to invoke the underlying function.
The purpose of this commit is to add a highly optimized way to enter a
wasm module, performing type checks up front and avoiding all the costs
of boxing and unboxing arguments within a `Val`. In general this should
be much more optimized than the previous `call` API for entering a wasm
module, if the signature is statically known.
* rustfmt
* Remove stray debugging
* Remove the `jit_function_registry` global state
This commit removes on the final pieces of global state in wasmtime
today, the `jit_function_registry` module. The purpose of this module is
to help translate a native backtrace with native program counters into a
wasm backtrace with module names, function names, and wasm module
indices. To that end this module retained a global map of function
ranges to this metadata information for each compiled function.
It turns out that we already had a `NAMES` global in the `wasmtime`
crate for symbolicating backtrace addresses, so this commit moves that
global into its own file and restructures the internals to account for
program counter ranges as well. The general set of changes here are:
* Remove `jit_function_registry`
* Remove `NAMES`
* Create a new `frame_info` module which has a singleton global
registering compiled module's frame information.
* Update traps to use the `frame_info` module to symbolicate pcs,
directly extracting a `FrameInfo` from the module.
* Register and unregister information on a module level instead of on a
per-function level (at least in terms of locking granluarity).
This commit leaves the new `FRAME_INFO` global variable as the only
remaining "critical" global variable in `wasmtime`, which only exists
due to the API of `Trap` where it doesn't take in any extra context when
capturing a stack trace through which we could hang off frame
information. I'm thinking though that this is ok, and we can always
tweak the API of `Trap` in the future if necessary if we truly need to
accomodate this.
* Remove a lazy_static dep
* Add some comments and restructure
* Move `Func` to its own file
* Support `Func` imports with zero shims
This commit extends the `Func` type in the `wasmtime` crate with static
`wrap*` constructors. The goal of these constructors is to create a
`Func` type which has zero shims associated with it, creating as small
of a layer as possible between wasm code and calling imported Rust code.
This is achieved by creating an `extern "C"` shim function which matches
the ABI of what Cranelift will generate, and then the host function is
passed directly into an `InstanceHandle` to get called later. This also
enables enough inlining opportunities that LLVM will be able to see all
functions and inline everything to the point where your function is
called immediately from wasm, no questions asked.
* Document the `wasmtime::Instance` APIs
This documents oddities like the import list and export list and how to
match them all up. Addtionally this largely just expands all the docs
related to `Instance` to get filled out.
This also moves the `set_signal_handler` functions into
platform-specific modules in order to follow Rust idioms about how to
expose platform-specific information. Additionally the methods are
marked `unsafe` because I figure anything having to do with signal
handling is `unsafe` inherently. I don't actually know what these
functions do, so they're currently still undocumented.
* Fix build of python bindings
* Fix some rebase conflicts
* Remove the `Context` type from `wasmtime`
This hasn't really ended up being used in all that many places and the
dependencies on it were pretty minimal. This commit removes it in favor
of simplifying its various users a bit and/or leveraging the
`Engine`/`Store` structures where possible.
* Run rustfmt
* Move the C API to a separate crate
This commit moves the C API from `crates/api/src/wasm.rs` to
`crates/capi/src/lib.rs` to be located in a separate crate. There's a
number of reasons for this:
* When a Rust program depends on the `wasmtime` crate, there's no need
to compile in the C API.
* This should improve compile times of the `wasmtime` crate since it's
not producing artifacts which aren't always used.
* The development of the C API can be guaranteed to only use the public
API of the `wasmtime` crate itself.
Some CI pieces are tweaked and this overall shouldn't have much impact
on users, it's intended that it's a cleanup/speedup for developers!
* Disable rustdoc/tests for capi
* Review feedback
* Add back in accidentally deleted comment
* More renamings
* Try to fix dotnet build
This continues #788 and literally removes the type from the public API
of the `wasmtime` crate, making it inaccessible to the outside world.
Now it's purely an implementation detail, yay!
* Remove unsafety from `Trap` API
This commit removes the `unsafe impl Send` for `Trap` by removing the
internal `HostRef` and leaving `HostRef` entirely as an implementation
detail of the C API.
cc #708
* Run rustfmt
* Remove the `Flags` type from `Config` API
This commit removes the final foreign type from the `Config` API in the
`wasmtime` crate. The cranelift `Flags` type is now expanded into
various options on the `Config` structure itself, all prefixed with
`cranelift_` since they're only relevant to the Cranelift backend. The
various changes here were:
* The `avoid_div_traps` feature is enabled by default since it seemed
that was done anywhere anyway.
* Enabling the wasm SIMD feature enables the requisite features in
Cranelift as well.
* A method for enabling the debug verifier has been added.
* A method for configuring the Cranelift optimization level, as well as
a corresponding enumeration, has been added.
* Assert that `Config` is both `Send` and `Sync`
* Remove usage of `CompilationStrategy` from `Config`
This commit removes the public API usage of the internal
`CompilationStrategy` enumeration from the `Config` type in the
`wasmtime` crate. To do this the `enum` was copied locally into the
crate and renamed `Strategy`. The high-level description of this change
is:
* The `Config::strategy` method now takes a locally-defined `Strategy`
enumeration instead of an internal type.
* The contents of `Strategy` are always the same, not relying on Cargo
features to indicate which variants are present. This avoids
unnecessary downstream `#[cfg]`.
* A `lightbeam` feature was added to the `wasmtime` crate itself to
lightbeam compilation support.
* The `Config::strategy` method is now fallible. It returns a runtime
error if support for the selected strategy wasn't compiled in.
* The `Strategy` enum is listed as `#[non_exhaustive]` so we can safely
add variants over time to it.
This reduces the public crate dependencies of the `wasmtime` crate
itself, removing the need to reach into internal crates even more!
cc #708
* Fix fuzz targets
* Update nightly used to build releases
* Run rustfmt
* Refactor the `types.rs` types and structures
A few changes applied along the way:
* Documentation added to most methods and types.
* Limits are now stored with the maximum as optional rather than a
sentinel u32 value for `None`.
* The `Name` type was removed in favor of just using a bare `String`.
* The `Extern` prefix in the varaints of `ExternType` has been removed
since it was redundant.
* Accessors of `ExternType` variants no longer panic, and unwrapping
versions were added with "unwrap" in the name.
* Fields and methods named `r#type` were renamed to `ty` to avoid
requiring a raw identifier to use them.
* Remove `fail-fast: false`
This was left around since the development of GitHub Actions for
wasmtime, but they're no longer needed!
* Fix compilation of the test-programs code
* Fix compilation of wasmtime-py package
* Run rustfmt
* Migrate back to `std::` stylistically
This commit moves away from idioms such as `alloc::` and `core::` as
imports of standard data structures and types. Instead it migrates all
crates to uniformly use `std::` for importing standard data structures
and types. This also removes the `std` and `core` features from all
crates to and removes any conditional checking for `feature = "std"`
All of this support was previously added in #407 in an effort to make
wasmtime/cranelift "`no_std` compatible". Unfortunately though this
change comes at a cost:
* The usage of `alloc` and `core` isn't idiomatic. Especially trying to
dual between types like `HashMap` from `std` as well as from
`hashbrown` causes imports to be surprising in some cases.
* Unfortunately there was no CI check that crates were `no_std`, so none
of them actually were. Many crates still imported from `std` or
depended on crates that used `std`.
It's important to note, however, that **this does not mean that wasmtime
will not run in embedded environments**. The style of the code today and
idioms aren't ready in Rust to support this degree of multiplexing and
makes it somewhat difficult to keep up with the style of `wasmtime`.
Instead it's intended that embedded runtime support will be added as
necessary. Currently only `std` is necessary to build `wasmtime`, and
platforms that natively need to execute `wasmtime` will need to use a
Rust target that supports `std`. Note though that not all of `std` needs
to be supported, but instead much of it could be configured off to
return errors, and `wasmtime` would be configured to gracefully handle
errors.
The goal of this PR is to move `wasmtime` back to idiomatic usage of
features/`std`/imports/etc and help development in the short-term.
Long-term when platform concerns arise (if any) they can be addressed by
moving back to `no_std` crates (but fixing the issues mentioned above)
or ensuring that the target in Rust has `std` available.
* Start filling out platform support doc
