5a006674c39b5003128b78bc9a92f8edc99ae45c
18 Commits
| Author | SHA1 | Message | Date | |
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Alex Crichton
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cd53bed898 |
Implement AOT compilation for components (#5160)
* Pull `Module` out of `ModuleTextBuilder` This commit is the first in what will likely be a number towards preparing for serializing a compiled component to bytes, a precompiled artifact. To that end my rough plan is to merge all of the compiled artifacts for a component into one large object file instead of having lots of separate object files and lots of separate mmaps to manage. To that end I plan on eventually using `ModuleTextBuilder` to build one large text section for all core wasm modules and trampolines, meaning that `ModuleTextBuilder` is no longer specific to one module. I've extracted out functionality such as function name calculation as well as relocation resolving (now a closure passed in) in preparation for this. For now this just keeps tests passing, and the trajectory for this should become more clear over the following commits. * Remove component-specific object emission This commit removes the `ComponentCompiler::emit_obj` function in favor of `Compiler::emit_obj`, now renamed `append_code`. This involved significantly refactoring code emission to take a flat list of functions into `append_code` and the caller is responsible for weaving together various "families" of functions and un-weaving them afterwards. * Consolidate ELF parsing in `CodeMemory` This commit moves the ELF file parsing and section iteration from `CompiledModule` into `CodeMemory` so one location keeps track of section ranges and such. This is in preparation for sharing much of this code with components which needs all the same sections to get tracked but won't be using `CompiledModule`. A small side benefit from this is that the section parsing done in `CodeMemory` and `CompiledModule` is no longer duplicated. * Remove separately tracked traps in components Previously components would generate an "always trapping" function and the metadata around which pc was allowed to trap was handled manually for components. With recent refactorings the Wasmtime-standard trap section in object files is now being generated for components as well which means that can be reused instead of custom-tracking this metadata. This commit removes the manual tracking for the `always_trap` functions and plumbs the necessary bits around to make components look more like modules. * Remove a now-unnecessary `Arc` in `Module` Not expected to have any measurable impact on performance, but complexity-wise this should make it a bit easier to understand the internals since there's no longer any need to store this somewhere else than its owner's location. * Merge compilation artifacts of components This commit is a large refactoring of the component compilation process to produce a single artifact instead of multiple binary artifacts. The core wasm compilation process is refactored as well to share as much code as necessary with the component compilation process. This method of representing a compiled component necessitated a few medium-sized changes internally within Wasmtime: * A new data structure was created, `CodeObject`, which represents metadata about a single compiled artifact. This is then stored as an `Arc` within a component and a module. For `Module` this is always uniquely owned and represents a shuffling around of data from one owner to another. For a `Component`, however, this is shared amongst all loaded modules and the top-level component. * The "module registry" which is used for symbolicating backtraces and for trap information has been updated to account for a single region of loaded code holding possibly multiple modules. This involved adding a second-level `BTreeMap` for now. This will likely slow down instantiation slightly but if it poses an issue in the future this should be able to be represented with a more clever data structure. This commit additionally solves a number of longstanding issues with components such as compiling only one host-to-wasm trampoline per signature instead of possibly once-per-module. Additionally the `SignatureCollection` registration now happens once-per-component instead of once-per-module-within-a-component. * Fix compile errors from prior commits * Support AOT-compiling components This commit adds support for AOT-compiled components in the same manner as `Module`, specifically adding: * `Engine::precompile_component` * `Component::serialize` * `Component::deserialize` * `Component::deserialize_file` Internally the support for components looks quite similar to `Module`. All the prior commits to this made adding the support here (unsurprisingly) easy. Components are represented as a single object file as are modules, and the functions for each module are all piled into the same object file next to each other (as are areas such as data sections). Support was also added here to quickly differentiate compiled components vs compiled modules via the `e_flags` field in the ELF header. * Prevent serializing exported modules on components The current representation of a module within a component means that the implementation of `Module::serialize` will not work if the module is exported from a component. The reason for this is that `serialize` doesn't actually do anything and simply returns the underlying mmap as a list of bytes. The mmap, however, has `.wasmtime.info` describing component metadata as opposed to this module's metadata. While rewriting this section could be implemented it's not so easy to do so and is otherwise seen as not super important of a feature right now anyway. * Fix windows build * Fix an unused function warning * Update crates/environ/src/compilation.rs Co-authored-by: Nick Fitzgerald <fitzgen@gmail.com> Co-authored-by: Nick Fitzgerald <fitzgen@gmail.com> |
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Pat Hickey
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12e4a1ba18 |
component model: async host function & embedding support (#5055)
* func_wrap_async typechecks
* func call async
* instantiate_async
* fixes
* async engine creation for tests
* start adding a component model test for async
* fix wrong check for async support, factor out Instance::new_started to an unchecked impl
* tests: wibbles
* component::Linker::func_wrap: replace IntoComponentFunc with directly accepting a closure
We find that this makes the Linker::func_wrap type signature much easier
to read. The IntoComponentFunc abstraction was adding a lot of weight to
"splat" a set of arguments from a tuple of types into individual
arguments to the closure. Additionally, making the StoreContextMut
argument optional, or the Result<return> optional, wasn't very
worthwhile.
* Fixes for the new style of closure required by component::Linker::func_wrap
* future of result of return
* add Linker::instantiate_async and {Typed}Func::post_return_async
* fix fuzzing generator
* note optimisation opportunity
* simplify test
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Alex Crichton
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29c7de7340 |
Update wasm-tools dependencies (#4970)
* Update wasm-tools dependencies This update brings in a number of features such as: * The component model binary format and AST has been slightly adjusted in a few locations. Names are dropped from parameters/results now in the internal representation since they were not used anyway. At this time the ability to bind a multi-return function has not been exposed. * The `wasmparser` validator pass will now share allocations with prior functions, providing what's probably a very minor speedup for Wasmtime itself. * The text format for many component-related tests now requires named parameters. * Some new relaxed-simd instructions are updated to be ignored. I hope to have a follow-up to expose the multi-return ability to the embedding API of components. * Update audit information for new crates |
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Alex Crichton
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650979ae40 |
Implement strings in adapter modules (#4623)
* Implement strings in adapter modules This commit is a hefty addition to Wasmtime's support for the component model. This implements the final remaining type (in the current type hierarchy) unimplemented in adapter module trampolines: strings. Strings are the most complicated type to implement in adapter trampolines because they are highly structured chunks of data in memory (according to specific encodings). Additionally each lift/lower operation can choose its own encoding for strings meaning that Wasmtime, the host, may have to convert between any pairwise ordering of string encodings. The `CanonicalABI.md` in the component-model repo in general specifies all the fiddly bits of string encoding so there's not a ton of wiggle room for Wasmtime to get creative. This PR largely "just" implements that. The high-level architecture of this implementation is: * Fused adapters are first identified to determine src/dst string encodings. This statically fixes what transcoding operation is being performed. * The generated adapter will be responsible for managing calls to `realloc` and performing bounds checks. The adapter itself does not perform memory copies or validation of string contents, however. Instead each transcoding operation is modeled as an imported function into the adapter module. This means that the adapter module dynamically, during compile time, determines what string transcoders are needed. Note that an imported transcoder is not only parameterized over the transcoding operation but additionally which memory is the source and which is the destination. * The imported core wasm functions are modeled as a new `CoreDef::Transcoder` structure. These transcoders end up being small Cranelift-compiled trampolines. The Cranelift-compiled trampoline will load the actual base pointer of memory and add it to the relative pointers passed as function arguments. This trampoline then calls a transcoder "libcall" which enters Rust-defined functions for actual transcoding operations. * Each possible transcoding operation is implemented in Rust with a unique name and a unique signature depending on the needs of the transcoder. I've tried to document inline what each transcoder does. This means that the `Module::translate_string` in adapter modules is by far the largest translation method. The main reason for this is due to the management around calling the imported transcoder functions in the face of validating string pointer/lengths and performing the dance of `realloc`-vs-transcode at the right time. I've tried to ensure that each individual case in transcoding is documented well enough to understand what's going on as well. Additionally in this PR is a full implementation in the host for the `latin1+utf16` encoding which means that both lifting and lowering host strings now works with this encoding. Currently the implementation of each transcoder function is likely far from optimal. Where possible I've leaned on the standard library itself and for latin1-related things I'm leaning on the `encoding_rs` crate. I initially tried to implement everything with `encoding_rs` but was unable to uniformly do so easily. For now I settled on trying to get a known-correct (even in the face of endianness) implementation for all of these transcoders. If an when performance becomes an issue it should be possible to implement more optimized versions of each of these transcoding operations. Testing this commit has been somewhat difficult and my general plan, like with the `(list T)` type, is to rely heavily on fuzzing to cover the various cases here. In this PR though I've added a simple test that pushes some statically known strings through all the pairs of encodings between source and destination. I've attempted to pick "interesting" strings that one way or another stress the various paths in each transcoding operation to ideally get full branch coverage there. Additionally a suite of "negative" tests have also been added to ensure that validity of encoding is actually checked. * Fix a temporarily commented out case * Fix wasmtime-runtime tests * Update deny.toml configuration * Add `BSD-3-Clause` for the `encoding_rs` crate * Remove some unused licenses * Add an exemption for `encoding_rs` for now * Split up the `translate_string` method Move out all the closures and package up captured state into smaller lists of arguments. * Test out-of-bounds for zero-length strings |
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Joel Dice
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ed8908efcf |
implement fuzzing for component types (#4537)
This addresses #4307. For the static API we generate 100 arbitrary test cases at build time, each of which includes 0-5 parameter types, a result type, and a WAT fragment containing an imported function and an exported function. The exported function calls the imported function, which is implemented by the host. At runtime, the fuzz test selects a test case at random and feeds it zero or more sets of arbitrary parameters and results, checking that values which flow host-to-guest and guest-to-host make the transition unchanged. The fuzz test for the dynamic API follows a similar pattern, the only difference being that test cases are generated at runtime. Signed-off-by: Joel Dice <joel.dice@fermyon.com> |
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Alex Crichton
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ee5b192d35 |
Re-enable component model *.wast tests (#4577)
* Re-enable component model `*.wast` tests These accidentally stopped running as part of #4556 on CI since I forgot one more location to touch a feature gate. * Enable logging in component tests This is a small convenience to get log messages during testing for components by default. |
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Alex Crichton
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893fadb485 |
components: Fix support for 0-sized flags (#4560)
This commit goes through and updates support in the various argument passing routines to support 0-sized flags. A bit of a degenerate case but clarified in WebAssembly/component-model#76 as intentional. |
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Alex Crichton
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04631ad0af |
Unconditionally enable component-model tests (#4556)
* Unconditionally enable component-model tests * Remove an outdated test that wasn't previously being compiled * Fix a component model doc test * Try to decrease memory usage in qemu |
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Joel Dice
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7c67e620c4 |
support dynamic function calls in component model (#4442)
* support dynamic function calls in component model This addresses #4310, introducing a new `component::values::Val` type for representing component values dynamically, as well as `component::types::Type` for representing the corresponding interface types. It also adds a `call` method to `component::func::Func`, which takes a slice of `Val`s as parameters and returns a `Result<Val>` representing the result. Note that I've moved `post_return` and `call_raw` from `TypedFunc` to `Func` since there was nothing specific to `TypedFunc` about them, and I wanted to reuse them. The code in both is unchanged beyond the trivial tweaks to make them fit in their new home. Signed-off-by: Joel Dice <joel.dice@fermyon.com> * order variants and match cases more consistently Signed-off-by: Joel Dice <joel.dice@fermyon.com> * implement lift for String, Box<str>, etc. This also removes the redundant `store` parameter from `Type::load`. Signed-off-by: Joel Dice <joel.dice@fermyon.com> * implement code review feedback This fixes a few issues: - Bad offset calculation when lowering - Missing variant padding - Style issues regarding `types::Handle` - Missed opportunities to reuse `Lift` and `Lower` impls It also adds forwarding `Lift` impls for `Box<[T]>`, `Vec<T>`, etc. Signed-off-by: Joel Dice <joel.dice@fermyon.com> * move `new_*` methods to specific `types` structs Per review feedback, I've moved `Type::new_record` to `Record::new_val` and added a `Type::unwrap_record` method; likewise for the other kinds of types. Signed-off-by: Joel Dice <joel.dice@fermyon.com> * make tuple, option, and expected type comparisons recursive These types should compare as equal across component boundaries as long as their type parameters are equal. Signed-off-by: Joel Dice <joel.dice@fermyon.com> * improve error diagnostic in `Type::check` We now distinguish between more failure cases to provide an informative error message. Signed-off-by: Joel Dice <joel.dice@fermyon.com> * address review feedback - Remove `WasmStr::to_str_from_memory` and `WasmList::get_from_memory` - add `try_new` methods to various `values` types - avoid using `ExactSizeIterator::len` where we can't trust it - fix over-constrained bounds on forwarded `ComponentType` impls Signed-off-by: Joel Dice <joel.dice@fermyon.com> * rearrange code per review feedback - Move functions from `types` to `values` module so we can make certain struct fields private - Rename `try_new` to just `new` Signed-off-by: Joel Dice <joel.dice@fermyon.com> * remove special-case equality test for tuples, options, and expecteds Instead, I've added a FIXME comment and will open an issue to do recursive structural equality testing. Signed-off-by: Joel Dice <joel.dice@fermyon.com> |
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Alex Crichton
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76a2545a7f |
Implement nested instance exports for components (#4364)
This commit adds support to Wasmtime for components which themselves export instances. The support here adds new APIs for how instance exports are accessed in the embedding API. For now this is mostly just a first-pass where the API is somewhat confusing and has a lot of lifetimes. I'm hoping that over time we can figure out how to simplify this but for now it should at least be expressive enough for exploring the exports of an instance. |
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Joel Dice
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22fb3ecbbf |
add ComponentType/Lift/Lower derive macro for record types (#4337)
This is the first stage of implementing https://github.com/bytecodealliance/wasmtime/issues/4308, i.e. derive macros for `ComponentType`, `Lift`, and `Lower` for composite types in the component model. This stage only covers records; I expect the other composite types will follow a similar pattern. It borrows heavily from the work Jamey Sharp did in https://github.com/bytecodealliance/wasmtime/pull/4217. Thanks for that, and thanks to both Jamey and Alex Crichton for their excellent review feedback. Thanks also to Brian for pairing up on the initial draft. Signed-off-by: Joel Dice <joel.dice@fermyon.com> |
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Alex Crichton
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3339dd1f01 |
Implement the post-return attribute (#4297)
This commit implements the `post-return` feature of the canonical ABI in the component model. This attribute is an optionally-specified function which is to be executed after the return value has been processed by the caller to optionally clean-up the return value. This enables, for example, returning an allocated string and the host then knows how to clean it up to prevent memory leaks in the original module. The API exposed in this PR changes the prior `TypedFunc::call` API in behavior but not in its signature. Previously the `TypedFunc::call` method would set the `may_enter` flag on the way out, but now that operation is deferred until a new `TypedFunc::post_return` method is called. This means that once a method on an instance is invoked then nothing else can be done on the instance until the `post_return` method is called. Note that the method must be called irrespective of whether the `post-return` canonical ABI option was specified or not. Internally wasm will be invoked if necessary. This is a pretty wonky and unergonomic API to work with. For now I couldn't think of a better alternative that improved on the ergonomics. In the theory that the raw Wasmtime bindings for a component may not be used all that heavily (instead `wit-bindgen` would largely be used) I'm hoping that this isn't too much of an issue in the future. cc #4185 |
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Alex Crichton
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651f40855f |
Add support for nested components (#4285)
* Add support for nested components
This commit is an implementation of a number of features of the
component model including:
* Defining nested components
* Outer aliases to components and modules
* Instantiating nested components
The implementation here is intended to be a foundational pillar of
Wasmtime's component model support since recursion and nested components
are the bread-and-butter of the component model. At a high level the
intention for the component model implementation in Wasmtime has long
been that the recursive nature of components is "erased" at compile time
to something that's more optimized and efficient to process. This commit
ended up exemplifying this quite well where the vast majority of the
internal changes here are in the "compilation" phase of a component
rather than the runtime instantiation phase. The support in the
`wasmtime` crate, the runtime instantiation support, only had minor
updates here while the internals of translation have seen heavy updates.
The `translate` module was greatly refactored here in this commit.
Previously it would, as a component is parsed, create a final
`Component` to hand off to trampoline compilation and get persisted at
runtime. Instead now it's a thin layer over `wasmparser` which simply
records a list of `LocalInitializer` entries for how to instantiate the
component and its index spaces are built. This internal representation
of the instantiation of a component is pretty close to the binary format
intentionally.
Instead of performing dataflow legwork the `translate` phase of a
component is now responsible for two primary tasks:
1. All components and modules are discovered within a component. They're
assigned `Static{Component,Module}Index` depending on where they're
found and a `{Module,}Translation` is prepared for each one. This
"flattens" the recursive structure of the binary into an indexed list
processable later.
2. The lexical scope of components is managed here to implement outer
module and component aliases. This is a significant design
implementation because when closing over an outer component or module
that item may actually be imported or something like the result of a
previous instantiation. This means that the capture of
modules and components is both a lexical concern as well as a runtime
concern. The handling of the "runtime" bits are handled in the next
phase of compilation.
The next and currently final phase of compilation is a new pass where
much of the historical code in `translate.rs` has been moved to (but
heavily refactored). The goal of compilation is to produce one "flat"
list of initializers for a component (as happens prior to this PR) and
to achieve this an "inliner" phase runs which runs through the
instantiation process at compile time to produce a list of initializers.
This `inline` module is the main addition as part of this PR and is now
the workhorse for dataflow analysis and tracking what's actually
referring to what.
During the `inline` phase the local initializers recorded in the
`translate` phase are processed, in sequence, to instantiate a
component. Definitions of items are tracked to correspond to their root
definition which allows seeing across instantiation argument boundaries
and such. Handling "upvars" for component outer aliases is handled in
the `inline` phase as well by creating state for a component whenever a
component is defined as was recorded during the `translate` phase.
Finally this phase is chiefly responsible for doing all string-based
name resolution at compile time that it can. This means that at runtime
no string maps will need to be consulted for item exports and such.
The final result of inlining is a list of "global initializers" which is
a flat list processed during instantiation time. These are almost
identical to the initializers that were processed prior to this PR.
There are certainly still more gaps of the component model to implement
but this should be a major leg up in terms of functionality that
Wasmtime implements. This commit, however leaves behind a "hole" which
is not intended to be filled in at this time, namely importing and
exporting components at the "root" level from and to the host. This is
tracked and explained in more detail as part of #4283.
cc #4185 as this completes a number of items there
* Tweak code to work on stable without warning
* Review comments
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Alex Crichton
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7d7ddceb17 |
Update wasm-tools crates (#4246)
This commit updates the wasm-tools family of crates, notably pulling in the refactorings and updates from bytecodealliance/wasm-tools#621 for the latest iteration of the component model. This commit additionally updates all support for the component model for these changes, notably: * Many bits and pieces of type information was refactored. Many `FooTypeIndex` namings are now `TypeFooIndex`. Additionally there is now `TypeIndex` as well as `ComponentTypeIndex` for the two type index spaces in a component. * A number of new sections are now processed to handle the core and component variants. * Internal maps were split such as the `funcs` map into `component_funcs` and `funcs` (same for `instances`). * Canonical options are now processed individually instead of one bulk `into` definition. Overall this was not a major update to the internals of handling the component model in Wasmtime. Instead this was mostly a surface-level refactoring to make sure that everything lines up with the new binary format for components. * All text syntax used in tests was updated to the new syntax. |
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Alex Crichton
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0b4448a423 |
Validate alignment in the canonical ABI (#4238)
This commit updates the lifting and lowering done by Wasmtime to validate that alignment is all correct. Previously alignment was ignored because I wasn't sure how this would all work out. To be extra safe I haven't actually modified any loads/stores and they're all still unaligned. If this becomes a performance issue we can investigate aligned loads and stores but otherwise I believe the requisite locations have been guarded with traps and I've also added debug asserts to catch possible future mistakes. |
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Alex Crichton
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3ed6fae7b3 |
Add trampoline compilation support for lowered imports (#4206)
* Add trampoline compilation support for lowered imports This commit adds support to the component model implementation for compiling trampolines suitable for calling host imports. Currently this is purely just the compilation side of things, modifying the wasmtime-cranelift crate and additionally filling out a new `VMComponentOffsets` type (similar to `VMOffsets`). The actual creation of a `VMComponentContext` is still not performed and will be a subsequent PR. Internally though some tests are actually possible with this where we at least assert that compilation of a component and creation of everything in-memory doesn't panic or trip any assertions, so some tests are added here for that as well. * Fix some test errors |
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Alex Crichton
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140b83597b |
components: Implement the ability to call component exports (#4039)
* components: Implement the ability to call component exports This commit is an implementation of the typed method of calling component exports. This is intended to represent the most efficient way of calling a component in Wasmtime, similar to what `TypedFunc` represents today for core wasm. Internally this contains all the traits and implementations necessary to invoke component exports with any type signature (e.g. arbitrary parameters and/or results). The expectation is that for results we'll reuse all of this infrastructure except in reverse (arguments and results will be swapped when defining imports). Some features of this implementation are: * Arbitrary type hierarchies are supported * The Rust-standard `Option`, `Result`, `String`, `Vec<T>`, and tuple types all map down to the corresponding type in the component model. * Basic utf-16 string support is implemented as proof-of-concept to show what handling might look like. This will need further testing and benchmarking. * Arguments can be behind "smart pointers", so for example `&Rc<Arc<[u8]>>` corresponds to `list<u8>` in interface types. * Bulk copies from linear memory never happen unless explicitly instructed to do so. The goal of this commit is to create the ability to actually invoke wasm components. This represents what is expected to be the performance threshold for these calls where it ideally should be optimal how WebAssembly is invoked. One major missing piece of this is a `#[derive]` of some sort to generate Rust types for arbitrary `*.wit` types such as custom records, variants, flags, unions, etc. The current trait impls for tuples and `Result<T, E>` are expected to have fleshed out most of what such a derive would look like. There are some downsides and missing pieces to this commit and method of calling components, however, such as: * Passing `&[u8]` to WebAssembly is currently not optimal. Ideally this compiles down to a `memcpy`-equivalent somewhere but that currently doesn't happen due to all the bounds checks of copying data into memory. I have been unsuccessful so far at getting these bounds checks to be removed. * There is no finalization at this time (the "post return" functionality in the canonical ABI). Implementing this should be relatively straightforward but at this time requires `wasmparser` changes to catch up with the current canonical ABI. * There is no guarantee that results of a wasm function will be validated. As results are consumed they are validated but this means that if function returns an invalid string which the host doesn't look at then no trap will be generated. This is probably not the intended semantics of hosts in the component model. * At this time there's no support for memory64 memories, just a bunch of `FIXME`s to get around to. It's expected that this won't be too onerous, however. Some extra care will need to ensure that the various methods related to size/alignment all optimize to the same thing they do today (e.g. constants). * The return value of a typed component function is either `T` or `Value<T>`, and it depends on the ABI details of `T` and whether it takes up more than one return value slot or not. This is an ABI-implementation detail which is being forced through to the API layer which is pretty unfortunate. For example if you say the return value of a function is `(u8, u32)` then it's a runtime type-checking error. I don't know of a great way to solve this at this time. Overall I'm feeling optimistic about this trajectory of implementing value lifting/lowering in Wasmtime. While there are a number of downsides none seem completely insurmountable. There's naturally still a good deal of work with the component model but this should be a significant step up towards implementing and testing the component model. * Review comments * Write tests for calling functions This commit adds a new test file for actually executing functions and testing their results. This is not written as a `*.wast` test yet since it's not 100% clear if that's the best way to do that for now (given that dynamic signatures aren't supported yet). The tests themselves could all largely be translated to `*.wast` testing in the future, though, if supported. Along the way a number of minor issues were fixed with lowerings with the bugs exposed here. * Fix an endian mistake * Fix a typo and the `memory.fill` instruction |
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Alex Crichton
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fcf6208750 |
Initial skeleton of some component model processing (#4005)
* Initial skeleton of some component model processing This commit is the first of what will likely be many to implement the component model proposal in Wasmtime. This will be structured as a series of incremental commits, most of which haven't been written yet. My hope is to make this incremental and over time to make this easier to review and easier to test each step in isolation. Here much of the skeleton of how components are going to work in Wasmtime is sketched out. This is not a complete implementation of the component model so it's not all that useful yet, but some things you can do are: * Process the type section into a representation amenable for working with in Wasmtime. * Process the module section and register core wasm modules. * Process the instance section for core wasm modules. * Process core wasm module imports. * Process core wasm instance aliasing. * Ability to compile a component with core wasm embedded. * Ability to instantiate a component with no imports. * Ability to get functions from this component. This is already starting to diverge from the previous module linking representation where a `Component` will try to avoid unnecessary metadata about the component and instead internally only have the bare minimum necessary to instantiate the module. My hope is we can avoid constructing most of the index spaces during instantiation only for it to all ge thrown away. Additionally I'm predicting that we'll need to see through processing where possible to know how to generate adapters and where they are fused. At this time you can't actually call a component's functions, and that's the next PR that I would like to make. * Add tests for the component model support This commit uses the recently updated wasm-tools crates to add tests for the component model added in the previous commit. This involved updating the `wasmtime-wast` crate for component-model changes. Currently the component support there is quite primitive, but enough to at least instantiate components and verify the internals of Wasmtime are all working correctly. Additionally some simple tests for the embedding API have also been added. |