Commit Graph

133 Commits

Author SHA1 Message Date
Kyle Brown
963d73a83b Add component model wasmtime feature to Docs.rs (#5558) 2023-01-11 16:42:18 +00:00
Alex Crichton
d9fdbfd50e Use the sym operator for inline assembly (#5459)
* Use the `sym` operator for inline assembly

Avoids extra `#[no_mangle]` functions and undue symbols being exposed
from Wasmtime. This is a newly stabilized feature in Rust 1.66.0. I've
also added a `rust-version` entry to the `wasmtime` crate to try to head
off possible reports in the future about odd error messages or usage of
unstable features if the rustc version is too old.

* Fix a s390x warning

* Add `rust-version` annotation to Wasmtime crate

As the other main entrypoint for embedders.
2022-12-16 20:12:24 +00:00
Alex Crichton
2329ecc341 Add a wasmtime::component::bindgen! macro (#5317)
* Import Wasmtime support from the `wit-bindgen` repo

This commit imports the `wit-bindgen-gen-host-wasmtime-rust` crate from
the `wit-bindgen` repository into the upstream Wasmtime repository. I've
chosen to not import the full history here since the crate is relatively
small and doesn't have a ton of complexity. While the history of the
crate is quite long the current iteration of the crate's history is
relatively short so there's not a ton of import there anyway. The
thinking is that this can now continue to evolve in-tree.

* Refactor `wasmtime-component-macro` a bit

Make room for a `wit_bindgen` macro to slot in.

* Add initial support for a `bindgen` macro

* Add tests for `wasmtime::component::bindgen!`

* Improve error forgetting `async` feature

* Add end-to-end tests for bindgen

* Add an audit of `unicase`

* Add a license to the test-helpers crate

* Add vet entry for `pulldown-cmark`

* Update publish script with new crate

* Try to fix publish script

* Update audits

* Update lock file
2022-12-06 13:06:00 -06:00
Alex Crichton
86acb9a438 Use workspace inheritance for some more dependencies (#5349)
Deduplicate some dependency directives through `[workspace.dependencies]`
2022-11-29 22:32:56 +00:00
Alex Crichton
3535acbf3b Merge pull request from GHSA-wh6w-3828-g9qf
* Unconditionally use `MemoryImageSlot`

This commit removes the internal branching within the pooling instance
allocator to sometimes use a `MemoryImageSlot` and sometimes now.
Instead this is now unconditionally used in all situations on all
platforms. This fixes an issue where the state of a slot could get
corrupted if modules being instantiated switched from having images to
not having an image or vice versa.

The bulk of this commit is the removal of the `memory-init-cow`
compile-time feature in addition to adding Windows support to the
`cow.rs` file.

* Fix compile on Unix

* Add a stricter assertion for static memory bounds

Double-check that when a memory is allocated the configuration required
is satisfied by the pooling allocator.
2022-11-10 11:34:38 -06:00
Alex Crichton
7b311004b5 Leverage Cargo's workspace inheritance feature (#4905)
* Leverage Cargo's workspace inheritance feature

This commit is an attempt to reduce the complexity of the Cargo
manifests in this repository with Cargo's workspace-inheritance feature
becoming stable in Rust 1.64.0. This feature allows specifying fields in
the root workspace `Cargo.toml` which are then reused throughout the
workspace. For example this PR shares definitions such as:

* All of the Wasmtime-family of crates now use `version.workspace =
  true` to have a single location which defines the version number.
* All crates use `edition.workspace = true` to have one default edition
  for the entire workspace.
* Common dependencies are listed in `[workspace.dependencies]` to avoid
  typing the same version number in a lot of different places (e.g. the
  `wasmparser = "0.89.0"` is now in just one spot.

Currently the workspace-inheritance feature doesn't allow having two
different versions to inherit, so all of the Cranelift-family of crates
still manually specify their version. The inter-crate dependencies,
however, are shared amongst the root workspace.

This feature can be seen as a method of "preprocessing" of sorts for
Cargo manifests. This will help us develop Wasmtime but shouldn't have
any actual impact on the published artifacts -- everything's dependency
lists are still the same.

* Fix wasi-crypto tests
2022-09-26 11:30:01 -05:00
Alex Crichton
65930640f8 Bump Wasmtime to 2.0.0 (#4874)
This commit replaces #4869 and represents the actual version bump that
should have happened had I remembered to bump the in-tree version of
Wasmtime to 1.0.0 prior to the branch-cut date. Alas!
2022-09-06 13:49:56 -05:00
Alex Crichton
57dca934ad Upgrade wasm-tools crates, namely the component model (#4715)
* Upgrade wasm-tools crates, namely the component model

This commit pulls in the latest versions of all of the `wasm-tools`
family of crates. There were two major changes that happened in
`wasm-tools` in the meantime:

* bytecodealliance/wasm-tools#697 - this commit introduced a new API for
  more efficiently reading binary operators from a wasm binary. The old
  `Operator`-based reading was left in place, however, and continues to
  be what Wasmtime uses. I hope to update Wasmtime in a future PR to use
  this new API, but for now the biggest change is...

* bytecodealliance/wasm-tools#703 - this commit was a major update to
  the component model AST. This commit almost entirely deals with the
  fallout of this change.

The changes made to the component model were:

1. The `unit` type no longer exists. This was generally a simple change
   where the `Unit` case in a few different locations were all removed.
2. The `expected` type was renamed to `result`. This similarly was
   relatively lightweight and mostly just a renaming on the surface. I
   took this opportunity to rename `val::Result` to `val::ResultVal` and
   `types::Result` to `types::ResultType` to avoid clashing with the
   standard library types. The `Option`-based types were handled with
   this as well.
3. The payload type of `variant` and `result` types are now optional.
   This affected many locations that calculate flat type
   representations, ABI information, etc. The `#[derive(ComponentType)]`
   macro now specifically handles Rust-defined `enum` types which have
   no payload to the equivalent in the component model.
4. Functions can now return multiple parameters. This changed the
   signature of invoking component functions because the return value is
   now bound by `ComponentNamedList` (renamed from `ComponentParams`).
   This had a large effect in the tests, fuzz test case generation, etc.
5. Function types with 2-or-more parameters/results must uniquely name
   all parameters/results. This mostly affected the text format used
   throughout the tests.

I haven't added specifically new tests for multi-return but I changed a
number of tests to use it. Additionally I've updated the fuzzers to all
exercise multi-return as well so I think we should get some good
coverage with that.

* Update version numbers

* Use crates.io
2022-08-17 16:17:34 +00:00
Benjamin Bouvier
8a9b1a9025 Implement an incremental compilation cache for Cranelift (#4551)
This is the implementation of https://github.com/bytecodealliance/wasmtime/issues/4155, using the "inverted API" approach suggested by @cfallin (thanks!) in Cranelift, and trait object to provide a backend for an all-included experience in Wasmtime. 

After the suggestion of Chris, `Function` has been split into mostly two parts:

- on the one hand, `FunctionStencil` contains all the fields required during compilation, and that act as a compilation cache key: if two function stencils are the same, then the result of their compilation (`CompiledCodeBase<Stencil>`) will be the same. This makes caching trivial, as the only thing to cache is the `FunctionStencil`.
- on the other hand, `FunctionParameters` contain the... function parameters that are required to finalize the result of compilation into a `CompiledCode` (aka `CompiledCodeBase<Final>`) with proper final relocations etc., by applying fixups and so on.

Most changes are here to accomodate those requirements, in particular that `FunctionStencil` should be `Hash`able to be used as a key in the cache:

- most source locations are now relative to a base source location in the function, and as such they're encoded as `RelSourceLoc` in the `FunctionStencil`. This required changes so that there's no need to explicitly mark a `SourceLoc` as the base source location, it's automatically detected instead the first time a non-default `SourceLoc` is set.
- user-defined external names in the `FunctionStencil` (aka before this patch `ExternalName::User { namespace, index }`) are now references into an external table of `UserExternalNameRef -> UserExternalName`, present in the `FunctionParameters`, and must be explicitly declared using `Function::declare_imported_user_function`.
- some refactorings have been made for function names:
  - `ExternalName` was used as the type for a `Function`'s name; while it thus allowed `ExternalName::Libcall` in this place, this would have been quite confusing to use it there. Instead, a new enum `UserFuncName` is introduced for this name, that's either a user-defined function name (the above `UserExternalName`) or a test case name.
  - The future of `ExternalName` is likely to become a full reference into the `FunctionParameters`'s mapping, instead of being "either a handle for user-defined external names, or the thing itself for other variants". I'm running out of time to do this, and this is not trivial as it implies touching ISLE which I'm less familiar with.

The cache computes a sha256 hash of the `FunctionStencil`, and uses this as the cache key. No equality check (using `PartialEq`) is performed in addition to the hash being the same, as we hope that this is sufficient data to avoid collisions.

A basic fuzz target has been introduced that tries to do the bare minimum:

- check that a function successfully compiled and cached will be also successfully reloaded from the cache, and returns the exact same function.
- check that a trivial modification in the external mapping of `UserExternalNameRef -> UserExternalName` hits the cache, and that other modifications don't hit the cache.
  - This last check is less efficient and less likely to happen, so probably should be rethought a bit.

Thanks to both @alexcrichton and @cfallin for your very useful feedback on Zulip.

Some numbers show that for a large wasm module we're using internally, this is a 20% compile-time speedup, because so many `FunctionStencil`s are the same, even within a single module. For a group of modules that have a lot of code in common, we get hit rates up to 70% when they're used together. When a single function changes in a wasm module, every other function is reloaded; that's still slower than I expect (between 10% and 50% of the overall compile time), so there's likely room for improvement. 

Fixes #4155.
2022-08-12 16:47:43 +00:00
Alex Crichton
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
2022-08-08 16:01:57 +00:00
wasmtime-publish
412fa04911 Bump Wasmtime to 0.41.0 (#4620)
Co-authored-by: Wasmtime Publish <wasmtime-publish@users.noreply.github.com>
2022-08-04 20:02:19 -05:00
Nick Fitzgerald
46782b18c2 wasmtime: Implement fast Wasm stack walking (#4431)
* Always preserve frame pointers in Wasmtime

This allows us to efficiently and simply capture Wasm stacks without maintaining
and synchronizing any safety-critical side tables between the compiler and the
runtime.

* wasmtime: Implement fast Wasm stack walking

Why do we want Wasm stack walking to be fast? Because we capture stacks whenever
there is a trap and traps actually happen fairly frequently with short-lived
programs and WASI's `exit`.

Previously, we would rely on generating the system unwind info (e.g.
`.eh_frame`) and using the system unwinder (via the `backtrace`crate) to walk
the full stack and filter out any non-Wasm stack frames. This can,
unfortunately, be slow for two primary reasons:

1. The system unwinder is doing `O(all-kinds-of-frames)` work rather than
`O(wasm-frames)` work.

2. System unwind info and the system unwinder need to be much more general than
a purpose-built stack walker for Wasm needs to be. It has to handle any kind of
stack frame that any compiler might emit where as our Wasm frames are emitted by
Cranelift and always have frame pointers. This translates into implementation
complexity and general overhead. There can also be unnecessary-for-our-use-cases
global synchronization and locks involved, further slowing down stack walking in
the presence of multiple threads trying to capture stacks in parallel.

This commit introduces a purpose-built stack walker for traversing just our Wasm
frames. To find all the sequences of Wasm-to-Wasm stack frames, and ignore
non-Wasm stack frames, we keep a linked list of `(entry stack pointer, exit
frame pointer)` pairs. This linked list is maintained via Wasm-to-host and
host-to-Wasm trampolines. Within a sequence of Wasm-to-Wasm calls, we can use
frame pointers (which Cranelift preserves) to find the next older Wasm frame on
the stack, and we keep doing this until we reach the entry stack pointer,
meaning that the next older frame will be a host frame.

The trampolines need to avoid a couple stumbling blocks. First, they need to be
compiled ahead of time, since we may not have access to a compiler at
runtime (e.g. if the `cranelift` feature is disabled) but still want to be able
to call functions that have already been compiled and get stack traces for those
functions. Usually this means we would compile the appropriate trampolines
inside `Module::new` and the compiled module object would hold the
trampolines. However, we *also* need to support calling host functions that are
wrapped into `wasmtime::Func`s and there doesn't exist *any* ahead-of-time
compiled module object to hold the appropriate trampolines:

```rust
// Define a host function.
let func_type = wasmtime::FuncType::new(
    vec![wasmtime::ValType::I32],
    vec![wasmtime::ValType::I32],
);
let func = Func::new(&mut store, func_type, |_, params, results| {
    // ...
    Ok(())
});

// Call that host function.
let mut results = vec![wasmtime::Val::I32(0)];
func.call(&[wasmtime::Val::I32(0)], &mut results)?;
```

Therefore, we define one host-to-Wasm trampoline and one Wasm-to-host trampoline
in assembly that work for all Wasm and host function signatures. These
trampolines are careful to only use volatile registers, avoid touching any
register that is an argument in the calling convention ABI, and tail call to the
target callee function. This allows forwarding any set of arguments and any
returns to and from the callee, while also allowing us to maintain our linked
list of Wasm stack and frame pointers before transferring control to the
callee. These trampolines are not used in Wasm-to-Wasm calls, only when crossing
the host-Wasm boundary, so they do not impose overhead on regular calls. (And if
using one trampoline for all host-Wasm boundary crossing ever breaks branch
prediction enough in the CPU to become any kind of bottleneck, we can do fun
things like have multiple copies of the same trampoline and choose a random copy
for each function, sharding the functions across branch predictor entries.)

Finally, this commit also ends the use of a synthetic `Module` and allocating a
stubbed out `VMContext` for host functions. Instead, we define a
`VMHostFuncContext` with its own magic value, similar to `VMComponentContext`,
specifically for host functions.

<h2>Benchmarks</h2>

<h3>Traps and Stack Traces</h3>

Large improvements to taking stack traces on traps, ranging from shaving off 64%
to 99.95% of the time it used to take.

<details>

```
multi-threaded-traps/0  time:   [2.5686 us 2.5808 us 2.5934 us]
                        thrpt:  [0.0000  elem/s 0.0000  elem/s 0.0000  elem/s]
                 change:
                        time:   [-85.419% -85.153% -84.869%] (p = 0.00 < 0.05)
                        thrpt:  [+560.90% +573.56% +585.84%]
                        Performance has improved.
Found 8 outliers among 100 measurements (8.00%)
  4 (4.00%) high mild
  4 (4.00%) high severe
multi-threaded-traps/1  time:   [2.9021 us 2.9167 us 2.9322 us]
                        thrpt:  [341.04 Kelem/s 342.86 Kelem/s 344.58 Kelem/s]
                 change:
                        time:   [-91.455% -91.294% -91.096%] (p = 0.00 < 0.05)
                        thrpt:  [+1023.1% +1048.6% +1070.3%]
                        Performance has improved.
Found 6 outliers among 100 measurements (6.00%)
  1 (1.00%) high mild
  5 (5.00%) high severe
multi-threaded-traps/2  time:   [2.9996 us 3.0145 us 3.0295 us]
                        thrpt:  [660.18 Kelem/s 663.47 Kelem/s 666.76 Kelem/s]
                 change:
                        time:   [-94.040% -93.910% -93.762%] (p = 0.00 < 0.05)
                        thrpt:  [+1503.1% +1542.0% +1578.0%]
                        Performance has improved.
Found 5 outliers among 100 measurements (5.00%)
  5 (5.00%) high severe
multi-threaded-traps/4  time:   [5.5768 us 5.6052 us 5.6364 us]
                        thrpt:  [709.68 Kelem/s 713.63 Kelem/s 717.25 Kelem/s]
                 change:
                        time:   [-93.193% -93.121% -93.052%] (p = 0.00 < 0.05)
                        thrpt:  [+1339.2% +1353.6% +1369.1%]
                        Performance has improved.
multi-threaded-traps/8  time:   [8.6408 us 9.1212 us 9.5438 us]
                        thrpt:  [838.24 Kelem/s 877.08 Kelem/s 925.84 Kelem/s]
                 change:
                        time:   [-94.754% -94.473% -94.202%] (p = 0.00 < 0.05)
                        thrpt:  [+1624.7% +1709.2% +1806.1%]
                        Performance has improved.
multi-threaded-traps/16 time:   [10.152 us 10.840 us 11.545 us]
                        thrpt:  [1.3858 Melem/s 1.4760 Melem/s 1.5761 Melem/s]
                 change:
                        time:   [-97.042% -96.823% -96.577%] (p = 0.00 < 0.05)
                        thrpt:  [+2821.5% +3048.1% +3281.1%]
                        Performance has improved.
Found 1 outliers among 100 measurements (1.00%)
  1 (1.00%) high mild

many-modules-registered-traps/1
                        time:   [2.6278 us 2.6361 us 2.6447 us]
                        thrpt:  [378.11 Kelem/s 379.35 Kelem/s 380.55 Kelem/s]
                 change:
                        time:   [-85.311% -85.108% -84.909%] (p = 0.00 < 0.05)
                        thrpt:  [+562.65% +571.51% +580.76%]
                        Performance has improved.
Found 9 outliers among 100 measurements (9.00%)
  3 (3.00%) high mild
  6 (6.00%) high severe
many-modules-registered-traps/8
                        time:   [2.6294 us 2.6460 us 2.6623 us]
                        thrpt:  [3.0049 Melem/s 3.0235 Melem/s 3.0425 Melem/s]
                 change:
                        time:   [-85.895% -85.485% -85.022%] (p = 0.00 < 0.05)
                        thrpt:  [+567.63% +588.95% +608.95%]
                        Performance has improved.
Found 8 outliers among 100 measurements (8.00%)
  3 (3.00%) high mild
  5 (5.00%) high severe
many-modules-registered-traps/64
                        time:   [2.6218 us 2.6329 us 2.6452 us]
                        thrpt:  [24.195 Melem/s 24.308 Melem/s 24.411 Melem/s]
                 change:
                        time:   [-93.629% -93.551% -93.470%] (p = 0.00 < 0.05)
                        thrpt:  [+1431.4% +1450.6% +1469.5%]
                        Performance has improved.
Found 3 outliers among 100 measurements (3.00%)
  3 (3.00%) high mild
many-modules-registered-traps/512
                        time:   [2.6569 us 2.6737 us 2.6923 us]
                        thrpt:  [190.17 Melem/s 191.50 Melem/s 192.71 Melem/s]
                 change:
                        time:   [-99.277% -99.268% -99.260%] (p = 0.00 < 0.05)
                        thrpt:  [+13417% +13566% +13731%]
                        Performance has improved.
Found 4 outliers among 100 measurements (4.00%)
  4 (4.00%) high mild
many-modules-registered-traps/4096
                        time:   [2.7258 us 2.7390 us 2.7535 us]
                        thrpt:  [1.4876 Gelem/s 1.4955 Gelem/s 1.5027 Gelem/s]
                 change:
                        time:   [-99.956% -99.955% -99.955%] (p = 0.00 < 0.05)
                        thrpt:  [+221417% +223380% +224881%]
                        Performance has improved.
Found 2 outliers among 100 measurements (2.00%)
  1 (1.00%) high mild
  1 (1.00%) high severe

many-stack-frames-traps/1
                        time:   [1.4658 us 1.4719 us 1.4784 us]
                        thrpt:  [676.39 Kelem/s 679.38 Kelem/s 682.21 Kelem/s]
                 change:
                        time:   [-90.368% -89.947% -89.586%] (p = 0.00 < 0.05)
                        thrpt:  [+860.23% +894.72% +938.21%]
                        Performance has improved.
Found 8 outliers among 100 measurements (8.00%)
  5 (5.00%) high mild
  3 (3.00%) high severe
many-stack-frames-traps/8
                        time:   [2.4772 us 2.4870 us 2.4973 us]
                        thrpt:  [3.2034 Melem/s 3.2167 Melem/s 3.2294 Melem/s]
                 change:
                        time:   [-85.550% -85.370% -85.199%] (p = 0.00 < 0.05)
                        thrpt:  [+575.65% +583.51% +592.03%]
                        Performance has improved.
Found 8 outliers among 100 measurements (8.00%)
  4 (4.00%) high mild
  4 (4.00%) high severe
many-stack-frames-traps/64
                        time:   [10.109 us 10.171 us 10.236 us]
                        thrpt:  [6.2525 Melem/s 6.2925 Melem/s 6.3309 Melem/s]
                 change:
                        time:   [-78.144% -77.797% -77.336%] (p = 0.00 < 0.05)
                        thrpt:  [+341.22% +350.38% +357.55%]
                        Performance has improved.
Found 7 outliers among 100 measurements (7.00%)
  5 (5.00%) high mild
  2 (2.00%) high severe
many-stack-frames-traps/512
                        time:   [126.16 us 126.54 us 126.96 us]
                        thrpt:  [4.0329 Melem/s 4.0461 Melem/s 4.0583 Melem/s]
                 change:
                        time:   [-65.364% -64.933% -64.453%] (p = 0.00 < 0.05)
                        thrpt:  [+181.32% +185.17% +188.71%]
                        Performance has improved.
Found 4 outliers among 100 measurements (4.00%)
  4 (4.00%) high severe
```

</details>

<h3>Calls</h3>

There is, however, a small regression in raw Wasm-to-host and host-to-Wasm call
performance due the new trampolines. It seems to be on the order of about 2-10
nanoseconds per call, depending on the benchmark.

I believe this regression is ultimately acceptable because

1. this overhead will be vastly dominated by whatever work a non-nop callee
actually does,

2. we will need these trampolines, or something like them, when implementing the
Wasm exceptions proposal to do things like translate Wasm's exceptions into
Rust's `Result`s,

3. and because the performance improvements to trapping and capturing stack
traces are of such a larger magnitude than this call regressions.

<details>

```
sync/no-hook/host-to-wasm - typed - nop
                        time:   [28.683 ns 28.757 ns 28.844 ns]
                        change: [+16.472% +17.183% +17.904%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 10 outliers among 100 measurements (10.00%)
  1 (1.00%) low mild
  4 (4.00%) high mild
  5 (5.00%) high severe
sync/no-hook/host-to-wasm - untyped - nop
                        time:   [42.515 ns 42.652 ns 42.841 ns]
                        change: [+12.371% +14.614% +17.462%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 11 outliers among 100 measurements (11.00%)
  1 (1.00%) high mild
  10 (10.00%) high severe
sync/no-hook/host-to-wasm - unchecked - nop
                        time:   [33.936 ns 34.052 ns 34.179 ns]
                        change: [+25.478% +26.938% +28.369%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 9 outliers among 100 measurements (9.00%)
  7 (7.00%) high mild
  2 (2.00%) high severe
sync/no-hook/host-to-wasm - typed - nop-params-and-results
                        time:   [34.290 ns 34.388 ns 34.502 ns]
                        change: [+40.802% +42.706% +44.526%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 13 outliers among 100 measurements (13.00%)
  5 (5.00%) high mild
  8 (8.00%) high severe
sync/no-hook/host-to-wasm - untyped - nop-params-and-results
                        time:   [62.546 ns 62.721 ns 62.919 ns]
                        change: [+2.5014% +3.6319% +4.8078%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 12 outliers among 100 measurements (12.00%)
  2 (2.00%) high mild
  10 (10.00%) high severe
sync/no-hook/host-to-wasm - unchecked - nop-params-and-results
                        time:   [42.609 ns 42.710 ns 42.831 ns]
                        change: [+20.966% +22.282% +23.475%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 11 outliers among 100 measurements (11.00%)
  4 (4.00%) high mild
  7 (7.00%) high severe

sync/hook-sync/host-to-wasm - typed - nop
                        time:   [29.546 ns 29.675 ns 29.818 ns]
                        change: [+20.693% +21.794% +22.836%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 5 outliers among 100 measurements (5.00%)
  3 (3.00%) high mild
  2 (2.00%) high severe
sync/hook-sync/host-to-wasm - untyped - nop
                        time:   [45.448 ns 45.699 ns 45.961 ns]
                        change: [+17.204% +18.514% +19.590%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 14 outliers among 100 measurements (14.00%)
  4 (4.00%) high mild
  10 (10.00%) high severe
sync/hook-sync/host-to-wasm - unchecked - nop
                        time:   [34.334 ns 34.437 ns 34.558 ns]
                        change: [+23.225% +24.477% +25.886%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 12 outliers among 100 measurements (12.00%)
  5 (5.00%) high mild
  7 (7.00%) high severe
sync/hook-sync/host-to-wasm - typed - nop-params-and-results
                        time:   [36.594 ns 36.763 ns 36.974 ns]
                        change: [+41.967% +47.261% +52.086%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 12 outliers among 100 measurements (12.00%)
  3 (3.00%) high mild
  9 (9.00%) high severe
sync/hook-sync/host-to-wasm - untyped - nop-params-and-results
                        time:   [63.541 ns 63.831 ns 64.194 ns]
                        change: [-4.4337% -0.6855% +2.7134%] (p = 0.73 > 0.05)
                        No change in performance detected.
Found 8 outliers among 100 measurements (8.00%)
  6 (6.00%) high mild
  2 (2.00%) high severe
sync/hook-sync/host-to-wasm - unchecked - nop-params-and-results
                        time:   [43.968 ns 44.169 ns 44.437 ns]
                        change: [+18.772% +21.802% +24.623%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 15 outliers among 100 measurements (15.00%)
  3 (3.00%) high mild
  12 (12.00%) high severe

async/no-hook/host-to-wasm - typed - nop
                        time:   [4.9612 us 4.9743 us 4.9889 us]
                        change: [+9.9493% +11.911% +13.502%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 10 outliers among 100 measurements (10.00%)
  6 (6.00%) high mild
  4 (4.00%) high severe
async/no-hook/host-to-wasm - untyped - nop
                        time:   [5.0030 us 5.0211 us 5.0439 us]
                        change: [+10.841% +11.873% +12.977%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 10 outliers among 100 measurements (10.00%)
  3 (3.00%) high mild
  7 (7.00%) high severe
async/no-hook/host-to-wasm - typed - nop-params-and-results
                        time:   [4.9273 us 4.9468 us 4.9700 us]
                        change: [+4.7381% +6.8445% +8.8238%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 14 outliers among 100 measurements (14.00%)
  5 (5.00%) high mild
  9 (9.00%) high severe
async/no-hook/host-to-wasm - untyped - nop-params-and-results
                        time:   [5.1151 us 5.1338 us 5.1555 us]
                        change: [+9.5335% +11.290% +13.044%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 16 outliers among 100 measurements (16.00%)
  3 (3.00%) high mild
  13 (13.00%) high severe

async/hook-sync/host-to-wasm - typed - nop
                        time:   [4.9330 us 4.9394 us 4.9467 us]
                        change: [+10.046% +11.038% +12.035%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 12 outliers among 100 measurements (12.00%)
  5 (5.00%) high mild
  7 (7.00%) high severe
async/hook-sync/host-to-wasm - untyped - nop
                        time:   [5.0073 us 5.0183 us 5.0310 us]
                        change: [+9.3828% +10.565% +11.752%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 8 outliers among 100 measurements (8.00%)
  3 (3.00%) high mild
  5 (5.00%) high severe
async/hook-sync/host-to-wasm - typed - nop-params-and-results
                        time:   [4.9610 us 4.9839 us 5.0097 us]
                        change: [+9.0857% +11.513% +14.359%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 13 outliers among 100 measurements (13.00%)
  7 (7.00%) high mild
  6 (6.00%) high severe
async/hook-sync/host-to-wasm - untyped - nop-params-and-results
                        time:   [5.0995 us 5.1272 us 5.1617 us]
                        change: [+9.3600% +11.506% +13.809%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 10 outliers among 100 measurements (10.00%)
  6 (6.00%) high mild
  4 (4.00%) high severe

async-pool/no-hook/host-to-wasm - typed - nop
                        time:   [2.4242 us 2.4316 us 2.4396 us]
                        change: [+7.8756% +8.8803% +9.8346%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 8 outliers among 100 measurements (8.00%)
  5 (5.00%) high mild
  3 (3.00%) high severe
async-pool/no-hook/host-to-wasm - untyped - nop
                        time:   [2.5102 us 2.5155 us 2.5210 us]
                        change: [+12.130% +13.194% +14.270%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 12 outliers among 100 measurements (12.00%)
  4 (4.00%) high mild
  8 (8.00%) high severe
async-pool/no-hook/host-to-wasm - typed - nop-params-and-results
                        time:   [2.4203 us 2.4310 us 2.4440 us]
                        change: [+4.0380% +6.3623% +8.7534%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 14 outliers among 100 measurements (14.00%)
  5 (5.00%) high mild
  9 (9.00%) high severe
async-pool/no-hook/host-to-wasm - untyped - nop-params-and-results
                        time:   [2.5501 us 2.5593 us 2.5700 us]
                        change: [+8.8802% +10.976% +12.937%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 16 outliers among 100 measurements (16.00%)
  5 (5.00%) high mild
  11 (11.00%) high severe

async-pool/hook-sync/host-to-wasm - typed - nop
                        time:   [2.4135 us 2.4190 us 2.4254 us]
                        change: [+8.3640% +9.3774% +10.435%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 11 outliers among 100 measurements (11.00%)
  6 (6.00%) high mild
  5 (5.00%) high severe
async-pool/hook-sync/host-to-wasm - untyped - nop
                        time:   [2.5172 us 2.5248 us 2.5357 us]
                        change: [+11.543% +12.750% +13.982%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 8 outliers among 100 measurements (8.00%)
  1 (1.00%) high mild
  7 (7.00%) high severe
async-pool/hook-sync/host-to-wasm - typed - nop-params-and-results
                        time:   [2.4214 us 2.4353 us 2.4532 us]
                        change: [+1.5158% +5.0872% +8.6765%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 15 outliers among 100 measurements (15.00%)
  2 (2.00%) high mild
  13 (13.00%) high severe
async-pool/hook-sync/host-to-wasm - untyped - nop-params-and-results
                        time:   [2.5499 us 2.5607 us 2.5748 us]
                        change: [+10.146% +12.459% +14.919%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 18 outliers among 100 measurements (18.00%)
  3 (3.00%) high mild
  15 (15.00%) high severe

sync/no-hook/wasm-to-host - nop - typed
                        time:   [6.6135 ns 6.6288 ns 6.6452 ns]
                        change: [+37.927% +38.837% +39.869%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 7 outliers among 100 measurements (7.00%)
  2 (2.00%) high mild
  5 (5.00%) high severe
sync/no-hook/wasm-to-host - nop-params-and-results - typed
                        time:   [15.930 ns 15.993 ns 16.067 ns]
                        change: [+3.9583% +5.6286% +7.2430%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 12 outliers among 100 measurements (12.00%)
  11 (11.00%) high mild
  1 (1.00%) high severe
sync/no-hook/wasm-to-host - nop - untyped
                        time:   [20.596 ns 20.640 ns 20.690 ns]
                        change: [+4.3293% +5.2047% +6.0935%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 10 outliers among 100 measurements (10.00%)
  5 (5.00%) high mild
  5 (5.00%) high severe
sync/no-hook/wasm-to-host - nop-params-and-results - untyped
                        time:   [42.659 ns 42.882 ns 43.159 ns]
                        change: [-2.1466% -0.5079% +1.2554%] (p = 0.58 > 0.05)
                        No change in performance detected.
Found 15 outliers among 100 measurements (15.00%)
  1 (1.00%) high mild
  14 (14.00%) high severe
sync/no-hook/wasm-to-host - nop - unchecked
                        time:   [10.671 ns 10.691 ns 10.713 ns]
                        change: [+83.911% +87.620% +92.062%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 9 outliers among 100 measurements (9.00%)
  2 (2.00%) high mild
  7 (7.00%) high severe
sync/no-hook/wasm-to-host - nop-params-and-results - unchecked
                        time:   [11.136 ns 11.190 ns 11.263 ns]
                        change: [-29.719% -28.446% -27.029%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 14 outliers among 100 measurements (14.00%)
  4 (4.00%) high mild
  10 (10.00%) high severe

sync/hook-sync/wasm-to-host - nop - typed
                        time:   [6.7964 ns 6.8087 ns 6.8226 ns]
                        change: [+21.531% +24.206% +27.331%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 14 outliers among 100 measurements (14.00%)
  4 (4.00%) high mild
  10 (10.00%) high severe
sync/hook-sync/wasm-to-host - nop-params-and-results - typed
                        time:   [15.865 ns 15.921 ns 15.985 ns]
                        change: [+4.8466% +6.3330% +7.8317%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 16 outliers among 100 measurements (16.00%)
  3 (3.00%) high mild
  13 (13.00%) high severe
sync/hook-sync/wasm-to-host - nop - untyped
                        time:   [21.505 ns 21.587 ns 21.677 ns]
                        change: [+8.0908% +9.1943% +10.254%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 8 outliers among 100 measurements (8.00%)
  4 (4.00%) high mild
  4 (4.00%) high severe
sync/hook-sync/wasm-to-host - nop-params-and-results - untyped
                        time:   [44.018 ns 44.128 ns 44.261 ns]
                        change: [-1.4671% -0.0458% +1.2443%] (p = 0.94 > 0.05)
                        No change in performance detected.
Found 14 outliers among 100 measurements (14.00%)
  5 (5.00%) high mild
  9 (9.00%) high severe
sync/hook-sync/wasm-to-host - nop - unchecked
                        time:   [11.264 ns 11.326 ns 11.387 ns]
                        change: [+80.225% +81.659% +83.068%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 6 outliers among 100 measurements (6.00%)
  3 (3.00%) high mild
  3 (3.00%) high severe
sync/hook-sync/wasm-to-host - nop-params-and-results - unchecked
                        time:   [11.816 ns 11.865 ns 11.920 ns]
                        change: [-29.152% -28.040% -26.957%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 14 outliers among 100 measurements (14.00%)
  8 (8.00%) high mild
  6 (6.00%) high severe

async/no-hook/wasm-to-host - nop - typed
                        time:   [6.6221 ns 6.6385 ns 6.6569 ns]
                        change: [+43.618% +44.755% +45.965%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 13 outliers among 100 measurements (13.00%)
  6 (6.00%) high mild
  7 (7.00%) high severe
async/no-hook/wasm-to-host - nop-params-and-results - typed
                        time:   [15.884 ns 15.929 ns 15.983 ns]
                        change: [+3.5987% +5.2053% +6.7846%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 16 outliers among 100 measurements (16.00%)
  3 (3.00%) high mild
  13 (13.00%) high severe
async/no-hook/wasm-to-host - nop - untyped
                        time:   [20.615 ns 20.702 ns 20.821 ns]
                        change: [+6.9799% +8.1212% +9.2819%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 10 outliers among 100 measurements (10.00%)
  2 (2.00%) high mild
  8 (8.00%) high severe
async/no-hook/wasm-to-host - nop-params-and-results - untyped
                        time:   [41.956 ns 42.207 ns 42.521 ns]
                        change: [-4.3057% -2.7730% -1.2428%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 14 outliers among 100 measurements (14.00%)
  3 (3.00%) high mild
  11 (11.00%) high severe
async/no-hook/wasm-to-host - nop - unchecked
                        time:   [10.440 ns 10.474 ns 10.513 ns]
                        change: [+83.959% +85.826% +87.541%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 11 outliers among 100 measurements (11.00%)
  5 (5.00%) high mild
  6 (6.00%) high severe
async/no-hook/wasm-to-host - nop-params-and-results - unchecked
                        time:   [11.476 ns 11.512 ns 11.554 ns]
                        change: [-29.857% -28.383% -26.978%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 12 outliers among 100 measurements (12.00%)
  1 (1.00%) low mild
  6 (6.00%) high mild
  5 (5.00%) high severe
async/no-hook/wasm-to-host - nop - async-typed
                        time:   [26.427 ns 26.478 ns 26.532 ns]
                        change: [+6.5730% +7.4676% +8.3983%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 9 outliers among 100 measurements (9.00%)
  2 (2.00%) high mild
  7 (7.00%) high severe
async/no-hook/wasm-to-host - nop-params-and-results - async-typed
                        time:   [28.557 ns 28.693 ns 28.880 ns]
                        change: [+1.9099% +3.7332% +5.9731%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 15 outliers among 100 measurements (15.00%)
  1 (1.00%) high mild
  14 (14.00%) high severe

async/hook-sync/wasm-to-host - nop - typed
                        time:   [6.7488 ns 6.7630 ns 6.7784 ns]
                        change: [+19.935% +22.080% +23.683%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 9 outliers among 100 measurements (9.00%)
  4 (4.00%) high mild
  5 (5.00%) high severe
async/hook-sync/wasm-to-host - nop-params-and-results - typed
                        time:   [15.928 ns 16.031 ns 16.149 ns]
                        change: [+5.5188% +6.9567% +8.3839%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 11 outliers among 100 measurements (11.00%)
  9 (9.00%) high mild
  2 (2.00%) high severe
async/hook-sync/wasm-to-host - nop - untyped
                        time:   [21.930 ns 22.114 ns 22.296 ns]
                        change: [+4.6674% +7.7588% +10.375%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 4 outliers among 100 measurements (4.00%)
  3 (3.00%) high mild
  1 (1.00%) high severe
async/hook-sync/wasm-to-host - nop-params-and-results - untyped
                        time:   [42.684 ns 42.858 ns 43.081 ns]
                        change: [-5.2957% -3.4693% -1.6217%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 14 outliers among 100 measurements (14.00%)
  2 (2.00%) high mild
  12 (12.00%) high severe
async/hook-sync/wasm-to-host - nop - unchecked
                        time:   [11.026 ns 11.053 ns 11.086 ns]
                        change: [+70.751% +72.378% +73.961%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 10 outliers among 100 measurements (10.00%)
  5 (5.00%) high mild
  5 (5.00%) high severe
async/hook-sync/wasm-to-host - nop-params-and-results - unchecked
                        time:   [11.840 ns 11.900 ns 11.982 ns]
                        change: [-27.977% -26.584% -24.887%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 18 outliers among 100 measurements (18.00%)
  3 (3.00%) high mild
  15 (15.00%) high severe
async/hook-sync/wasm-to-host - nop - async-typed
                        time:   [27.601 ns 27.709 ns 27.882 ns]
                        change: [+8.1781% +9.1102% +10.030%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 11 outliers among 100 measurements (11.00%)
  2 (2.00%) low mild
  3 (3.00%) high mild
  6 (6.00%) high severe
async/hook-sync/wasm-to-host - nop-params-and-results - async-typed
                        time:   [28.955 ns 29.174 ns 29.413 ns]
                        change: [+1.1226% +3.0366% +5.1126%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 13 outliers among 100 measurements (13.00%)
  7 (7.00%) high mild
  6 (6.00%) high severe

async-pool/no-hook/wasm-to-host - nop - typed
                        time:   [6.5626 ns 6.5733 ns 6.5851 ns]
                        change: [+40.561% +42.307% +44.514%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 9 outliers among 100 measurements (9.00%)
  5 (5.00%) high mild
  4 (4.00%) high severe
async-pool/no-hook/wasm-to-host - nop-params-and-results - typed
                        time:   [15.820 ns 15.886 ns 15.969 ns]
                        change: [+4.1044% +5.7928% +7.7122%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 17 outliers among 100 measurements (17.00%)
  4 (4.00%) high mild
  13 (13.00%) high severe
async-pool/no-hook/wasm-to-host - nop - untyped
                        time:   [20.481 ns 20.521 ns 20.566 ns]
                        change: [+6.7962% +7.6950% +8.7612%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 11 outliers among 100 measurements (11.00%)
  6 (6.00%) high mild
  5 (5.00%) high severe
async-pool/no-hook/wasm-to-host - nop-params-and-results - untyped
                        time:   [41.834 ns 41.998 ns 42.189 ns]
                        change: [-3.8185% -2.2687% -0.7541%] (p = 0.01 < 0.05)
                        Change within noise threshold.
Found 13 outliers among 100 measurements (13.00%)
  3 (3.00%) high mild
  10 (10.00%) high severe
async-pool/no-hook/wasm-to-host - nop - unchecked
                        time:   [10.353 ns 10.380 ns 10.414 ns]
                        change: [+82.042% +84.591% +87.205%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 7 outliers among 100 measurements (7.00%)
  4 (4.00%) high mild
  3 (3.00%) high severe
async-pool/no-hook/wasm-to-host - nop-params-and-results - unchecked
                        time:   [11.123 ns 11.168 ns 11.228 ns]
                        change: [-30.813% -29.285% -27.874%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 12 outliers among 100 measurements (12.00%)
  11 (11.00%) high mild
  1 (1.00%) high severe
async-pool/no-hook/wasm-to-host - nop - async-typed
                        time:   [27.442 ns 27.528 ns 27.638 ns]
                        change: [+7.5215% +9.9795% +12.266%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 18 outliers among 100 measurements (18.00%)
  3 (3.00%) high mild
  15 (15.00%) high severe
async-pool/no-hook/wasm-to-host - nop-params-and-results - async-typed
                        time:   [29.014 ns 29.148 ns 29.312 ns]
                        change: [+2.0227% +3.4722% +4.9047%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 7 outliers among 100 measurements (7.00%)
  6 (6.00%) high mild
  1 (1.00%) high severe

async-pool/hook-sync/wasm-to-host - nop - typed
                        time:   [6.7916 ns 6.8116 ns 6.8325 ns]
                        change: [+20.937% +22.050% +23.281%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 11 outliers among 100 measurements (11.00%)
  5 (5.00%) high mild
  6 (6.00%) high severe
async-pool/hook-sync/wasm-to-host - nop-params-and-results - typed
                        time:   [15.917 ns 15.975 ns 16.051 ns]
                        change: [+4.6404% +6.4217% +8.3075%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 16 outliers among 100 measurements (16.00%)
  5 (5.00%) high mild
  11 (11.00%) high severe
async-pool/hook-sync/wasm-to-host - nop - untyped
                        time:   [21.558 ns 21.612 ns 21.679 ns]
                        change: [+8.1158% +9.1409% +10.217%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 9 outliers among 100 measurements (9.00%)
  2 (2.00%) high mild
  7 (7.00%) high severe
async-pool/hook-sync/wasm-to-host - nop-params-and-results - untyped
                        time:   [42.475 ns 42.614 ns 42.775 ns]
                        change: [-6.3613% -4.4709% -2.7647%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 18 outliers among 100 measurements (18.00%)
  3 (3.00%) high mild
  15 (15.00%) high severe
async-pool/hook-sync/wasm-to-host - nop - unchecked
                        time:   [11.150 ns 11.195 ns 11.247 ns]
                        change: [+74.424% +77.056% +79.811%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 14 outliers among 100 measurements (14.00%)
  3 (3.00%) high mild
  11 (11.00%) high severe
async-pool/hook-sync/wasm-to-host - nop-params-and-results - unchecked
                        time:   [11.639 ns 11.695 ns 11.760 ns]
                        change: [-30.212% -29.023% -27.954%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 15 outliers among 100 measurements (15.00%)
  7 (7.00%) high mild
  8 (8.00%) high severe
async-pool/hook-sync/wasm-to-host - nop - async-typed
                        time:   [27.480 ns 27.712 ns 27.984 ns]
                        change: [+2.9764% +6.5061% +9.8914%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 8 outliers among 100 measurements (8.00%)
  6 (6.00%) high mild
  2 (2.00%) high severe
async-pool/hook-sync/wasm-to-host - nop-params-and-results - async-typed
                        time:   [29.218 ns 29.380 ns 29.600 ns]
                        change: [+5.2283% +7.7247% +10.822%] (p = 0.00 < 0.05)
                        Performance has regressed.
Found 16 outliers among 100 measurements (16.00%)
  2 (2.00%) high mild
  14 (14.00%) high severe
```

</details>

* Add s390x support for frame pointer-based stack walking

* wasmtime: Allow `Caller::get_export` to get all exports

* fuzzing: Add a fuzz target to check that our stack traces are correct

We generate Wasm modules that keep track of their own stack as they call and
return between functions, and then we periodically check that if the host
captures a backtrace, it matches what the Wasm module has recorded.

* Remove VM offsets for `VMHostFuncContext` since it isn't used by JIT code

* Add doc comment with stack walking implementation notes

* Document the extra state that can be passed to `wasmtime_runtime::Backtrace` methods

* Add extensive comments for stack walking function

* Factor architecture-specific bits of stack walking out into modules

* Initialize store-related fields in a vmctx to null when there is no store yet

Rather than leaving them as uninitialized data.

* Use `set_callee` instead of manually setting the vmctx field

* Use a more informative compile error message for unsupported architectures

* Document unsafety of `prepare_host_to_wasm_trampoline`

* Use `bti c` instead of `hint #34` in inline aarch64 assembly

* Remove outdated TODO comment

* Remove setting of `last_wasm_exit_fp` in `set_jit_trap`

This is no longer needed as the value is plumbed through to the backtrace code
directly now.

* Only set the stack limit once, in the face of re-entrancy into Wasm

* Add comments for s390x-specific stack walking bits

* Use the helper macro for all libcalls

If we forget to use it, and then trigger a GC from the libcall, that means we
could miss stack frames when walking the stack, fail to find live GC refs, and
then get use after free bugs. Much less risky to always use the helper macro
that takes care of all of that for us.

* Use the `asm_sym!` macro in Wasm-to-libcall trampolines

This macro handles the macOS-specific underscore prefix stuff for us.

* wasmtime: add size and align to `externref` assertion error message

* Extend the `stacks` fuzzer to have host frames in between Wasm frames

This way we get one or more contiguous sequences of Wasm frames on the stack,
instead of exactly one.

* Add documentation for aarch64-specific backtrace helpers

* Clarify that we only support little-endian aarch64 in trampoline comment

* Use `.machine z13` in s390x assembly file

Since apparently our CI machines have pretty old assemblers that don't have
`.machine z14`. This should be fine though since these trampolines don't make
use of anything that is introduced in z14.

* Fix aarch64 build

* Fix macOS build

* Document the `asm_sym!` macro

* Add windows support to the `wasmtime-asm-macros` crate

* Add windows support to host<--->Wasm trampolines

* Fix trap handler build on windows

* Run `rustfmt` on s390x trampoline source file

* Temporarily disable some assertions about a trap's backtrace in the component model tests

Follow up to re-enable this and fix the associated issue:
https://github.com/bytecodealliance/wasmtime/issues/4535

* Refactor libcall definitions with less macros

This refactors the `libcall!` macro to use the
`foreach_builtin_function!` macro to define all of the trampolines.
Additionally the macro surrounding each libcall itself is no longer
necessary and helps avoid too many macros.

* Use `VMOpaqueContext::from_vm_host_func_context` in `VMHostFuncContext::new`

* Move `backtrace` module to be submodule of `traphandlers`

This avoids making some things `pub(crate)` in `traphandlers` that really
shouldn't be.

* Fix macOS aarch64 build

* Use "i64" instead of "word" in aarch64-specific file

* Save/restore entry SP and exit FP/return pointer in the face of panicking imported host functions

Also clean up assertions surrounding our saved entry/exit registers.

* Put "typed" vs "untyped" in the same position of call benchmark names

Regardless if we are doing wasm-to-host or host-to-wasm

* Fix stacks test case generator build for new `wasm-encoder`

* Fix build for s390x

* Expand libcalls in s390x asm

* Disable more parts of component tests now that backtrace assertions are a bit tighter

* Remove assertion that can maybe fail on s390x

Co-authored-by: Ulrich Weigand <ulrich.weigand@de.ibm.com>
Co-authored-by: Alex Crichton <alex@alexcrichton.com>
2022-07-28 15:46:14 -07:00
Alex Crichton
174b60dcf7 Add *.wast support for invoking components (#4526)
This commit builds on bytecodealliance/wasm-tools#690 to add support to
testing of the component model to execute functions when running
`*.wast` files. This support is all built on #4442 as functions are
invoked through a "dynamic" API. Right now the testing and integration
is fairly crude but I'm hoping that we can try to improve it over time
as necessary. For now this should provide a hopefully more convenient
syntax for unit tests and the like.
2022-07-27 21:02:16 +00:00
Joel Dice
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>
2022-07-25 13:38:48 -05:00
Alex Crichton
601e8f3094 Remove dependency on the region crate (#4407)
This commit removes Wasmtime's dependency on the `region` crate. The
motivation for this came about when I was updating dependencies and saw
that `region` had a new major version at 3.0.0 as opposed to our
currently used 2.3 track. In reviewing the use cases of `region` within
Wasmtime I found two trends in particular which motivated this commit:

* Some unix-specific areas of `wasmtime_runtime` use
  `rustix::mm::mprotect` instead of `region::protect` already. This
  means that the usage of `region::protect` for changing virtual memory
  protections was already inconsistent.

* Many uses of `region::protect` were already in unix-specific regions
  which could make use of `rustix`.

Overall I opted to remove the dependency on the `region` crate to avoid
chasing its versions over time. Unix-specific changes of protections
were easily changed to `rustix::mm::mprotect`. There were two locations
where a windows/unix split is now required and I subjectively ruled
"that seems ok". Finally removing `region` also meant that the "what is
the current page size" query needed to be inlined into
`wasmtime_runtime`, which I have also subjectively ruled "that seems
fine".

Finally one final refactoring here was that the `unix.rs` and `linux.rs`
split for the pooling allocator was merged. These two files already only
differed in one function so I slapped a `cfg_if!` in there to help
reduce the duplication.
2022-07-07 21:28:25 +00:00
Alex Crichton
9ae060a12a Update some dependency versions used by Wasmtime (#4405)
No major motivation here, mostly just dependency gardening.
2022-07-07 18:47:39 +00:00
Alex Crichton
41ba851a95 Bump versions of wasm-tools crates (#4380)
* Bump versions of wasm-tools crates

Note that this leaves new features in the component model, outer type
aliases for core wasm types, unimplemented for now.

* Move to crates.io-based versions of tools
2022-07-05 14:23:03 -05:00
Dan Gohman
371ae80ac3 Migrate most of wasmtime from lazy_static to once_cell (#4368)
* Update tracing-core to a version which doesn't depend on lazy-static.

* Update crossbeam-utils to a version that doesn't depend on lazy-static.

* Update crossbeam-epoch to a version that doesn't depend on lazy-static.

* Update clap to a version that doesn't depend on lazy-static.

* Convert Wasmtime's own use of lazy_static to once_cell.

* Make `GDB_REGISTRATION`'s comment a doc comment.

* Fix compilation on Windows.
2022-07-05 10:52:48 -07:00
wasmtime-publish
7c428bbd62 Bump Wasmtime to 0.40.0 (#4378)
Co-authored-by: Wasmtime Publish <wasmtime-publish@users.noreply.github.com>
2022-07-05 09:10:52 -05:00
Joel Dice
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>
2022-06-29 09:38:36 -05:00
Alex Crichton
df1502531d Migrate from winapi to windows-sys (#4346)
* Migrate from `winapi` to `windows-sys`

I believe that Microsoft itself is supporting the development of
`windows-sys` and it's also used by `cap-std` now so this switches
Wasmtime's dependencies on Windows APIs from the `winapi` crate to the
`windows-sys` crate. We still have `winapi` in our dependency graph but
that may get phased out over time.

* Make windows-sys a target-specific dependency
2022-06-28 18:02:41 +00:00
Alex Crichton
2f9d96cd00 Use Cargo's "namespace features" feature (#4293)
Cargo recently added the ability to have an optional dependency without
implicitly introducing a new named feature on a crate. This is triggered
with some new directives in the `[features]` section, specifically:

* The `dep:foo` syntax means that `foo` is activated but no implicit
  feature should be added named `foo`.

* Additionally `foo?/bar` means that the `bar` feature of `foo` is only
  activated if `foo` is otherwise activated elsewhere, for example a
  conditional activation.

These two features can help avoid extra feature names showing up that we
don't want (e.g. currently the `wasmtime` crate has a `rayon` feature)
and additionally can help avoid runtime dependencies in niche cases for
us (e.g. activating `all-arch` but disabling `cranelift` would
previously pull-in cranelift but no longer will).
2022-06-21 15:05:14 -05:00
Alex Crichton
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.
2022-06-09 11:16:07 -05:00
wasmtime-publish
55946704cb Bump Wasmtime to 0.39.0 (#4225)
Co-authored-by: Wasmtime Publish <wasmtime-publish@users.noreply.github.com>
2022-06-06 09:12:47 -05:00
Alex Crichton
2af358dd9c Add a VMComponentContext type and create it on instantiation (#4215)
* Add a `VMComponentContext` type and create it on instantiation

This commit fills out the `wasmtime-runtime` crate's support for
`VMComponentContext` and creates it as part of the instantiation
process. This moves a few maps that were temporarily allocated in an
`InstanceData` into the `VMComponentContext` and additionally reads the
canonical options data from there instead.

This type still won't be used in its "full glory" until the lowering of
host functions is completely implemented, however, which will be coming
in a future commit.

* Remove `DerefMut` implementation

* Rebase conflicts
2022-06-03 13:34:50 -05:00
Alex Crichton
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
2022-06-03 10:01:42 -05:00
Pat Hickey
bffce37050 make backtrace collection a Config field rather than a cargo feature (#4183)
* sorta working in runtime

* wasmtime-runtime: get rid of wasm-backtrace feature

* wasmtime: factor to make backtraces recording optional. not configurable yet

* get rid of wasm-backtrace features

* trap tests: now a Trap optionally contains backtrace

* eliminate wasm-backtrace feature

* code review fixes

* ci: no more wasm-backtrace feature

* c_api: backtraces always enabled

* config: unwind required by backtraces and ref types

* plumbed

* test that disabling backtraces works

* code review comments

* fuzzing generator: wasm_backtrace is a runtime config now

* doc fix
2022-05-25 12:25:50 -07:00
Alex Crichton
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.
2022-05-20 15:33:18 -05:00
Alex Crichton
89ccc56e46 Update the wasm-tools family of crates (#4165)
* Update the wasm-tools family of crates

This commit updates these crates as used by Wasmtime for the recently
published versions to pull in changes necessary to support the component
model. I've split this out from #4005 to make it clear what's impacted
here and #4005 can simply rebase on top of this to pick up the necessary
changes.

* More test fixes
2022-05-19 14:13:04 -05:00
wasmtime-publish
9a6854456d Bump Wasmtime to 0.38.0 (#4103)
Co-authored-by: Wasmtime Publish <wasmtime-publish@users.noreply.github.com>
2022-05-05 13:43:02 -05:00
Alex Crichton
871a9d93f2 Update some dependencies in Cargo.lock (#4081)
* Run a `cargo update` over our dependencies

This'll notably fix a `cargo audit` error where we have a pinned version
of the `regex` crate which has a CVE assigned to it.

* Update to `object` and `hashbrown` crates

Prune some duplicate versions showing up from the previous `cargo update`
2022-04-28 11:12:58 -05:00
Alex Crichton
3f3afb455e Remove support for userfaultfd (#4040)
This commit removes support for the `userfaultfd` or "uffd" syscall on
Linux. This support was originally added for users migrating from Lucet
to Wasmtime, but the recent developments of kernel-supported
copy-on-write support for memory initialization wound up being more
appropriate for these use cases than usefaultfd. The main reason for
moving to copy-on-write initialization are:

* The `userfaultfd` feature was never necessarily intended for this
  style of use case with wasm and was susceptible to subtle and rare
  bugs that were extremely difficult to track down. We were never 100%
  certain that there were kernel bugs related to userfaultfd but the
  suspicion never went away.

* Handling faults with userfaultfd was always slow and single-threaded.
  Only one thread could handle faults and traveling to user-space to
  handle faults is inherently slower than handling them all in the
  kernel. The single-threaded aspect in particular presented a
  significant scaling bottleneck for embeddings that want to run many
  wasm instances in parallel.

* One of the major benefits of userfaultfd was lazy initialization of
  wasm linear memory which is also achieved with the copy-on-write
  initialization support we have right now.

* One of the suspected benefits of userfaultfd was less frobbing of the
  kernel vma structures when wasm modules are instantiated. Currently
  the copy-on-write support has a mitigation where we attempt to reuse
  the memory images where possible to avoid changing vma structures.
  When comparing this to userfaultfd's performance it was found that
  kernel modifications of vmas aren't a worrisome bottleneck so
  copy-on-write is suitable for this as well.

Overall there are no remaining benefits that userfaultfd gives that
copy-on-write doesn't, and copy-on-write solves a major downsides of
userfaultfd, the scaling issue with a single faulting thread.
Additionally copy-on-write support seems much more robust in terms of
kernel implementation since it's only using standard memory-management
syscalls which are heavily exercised. Finally copy-on-write support
provides a new bonus where read-only memory in WebAssembly can be mapped
directly to the same kernel cache page, even amongst many wasm instances
of the same module, which was never possible with userfaultfd.

In light of all this it's expected that all users of userfaultfd should
migrate to the copy-on-write initialization of Wasmtime (which is
enabled by default).
2022-04-18 12:42:26 -05:00
Alex Crichton
d147802d51 Update wasm-tools crates (#3997)
* Update wasm-tools crates

This commit updates the wasm-tools family of crates as used in Wasmtime.
Notably this brings in the update which removes module linking support
as well as a number of internal refactorings around names and such
within wasmparser itself. This updates all of the wasm translation
support which binds to wasmparser as appropriate.

Other crates all had API-compatible changes for at least what Wasmtime
used so no further changes were necessary beyond updating version
requirements.

* Update a test expectation
2022-04-05 14:32:33 -05:00
wasmtime-publish
78a595ac88 Bump Wasmtime to 0.37.0 (#3994)
Co-authored-by: Wasmtime Publish <wasmtime-publish@users.noreply.github.com>
2022-04-05 09:24:28 -05:00
Alex Crichton
7b5176baea Upgrade all crates to the Rust 2021 edition (#3991)
* Upgrade all crates to the Rust 2021 edition

I've personally started using the new format strings for things like
`panic!("some message {foo}")` or similar and have been upgrading crates
on a case-by-case basis, but I think it probably makes more sense to go
ahead and blanket upgrade everything so 2021 features are always
available.

* Fix compile of the C API

* Fix a warning

* Fix another warning
2022-04-04 12:27:12 -05:00
Alex Crichton
c89dc55108 Add a two-week delay to Wasmtime's release process (#3955)
* Bump to 0.36.0

* Add a two-week delay to Wasmtime's release process

This commit is a proposal to update Wasmtime's release process with a
two-week delay from branching a release until it's actually officially
released. We've had two issues lately that came up which led to this proposal:

* In #3915 it was realized that changes just before the 0.35.0 release
  weren't enough for an embedding use case, but the PR didn't meet the
  expectations for a full patch release.

* At Fastly we were about to start rolling out a new version of Wasmtime
  when over the weekend the fuzz bug #3951 was found. This led to the
  desire internally to have a "must have been fuzzed for this long"
  period of time for Wasmtime changes which we felt were better
  reflected in the release process itself rather than something about
  Fastly's own integration with Wasmtime.

This commit updates the automation for releases to unconditionally
create a `release-X.Y.Z` branch on the 5th of every month. The actual
release from this branch is then performed on the 20th of every month,
roughly two weeks later. This should provide a period of time to ensure
that all changes in a release are fuzzed for at least two weeks and
avoid any further surprises. This should also help with any last-minute
changes made just before a release if they need tweaking since
backporting to a not-yet-released branch is much easier.

Overall there are some new properties about Wasmtime with this proposal
as well:

* The `main` branch will always have a section in `RELEASES.md` which is
  listed as "Unreleased" for us to fill out.
* The `main` branch will always be a version ahead of the latest
  release. For example it will be bump pre-emptively as part of the
  release process on the 5th where if `release-2.0.0` was created then
  the `main` branch will have 3.0.0 Wasmtime.
* Dates for major versions are automatically updated in the
  `RELEASES.md` notes.

The associated documentation for our release process is updated and the
various scripts should all be updated now as well with this commit.

* Add notes on a security patch

* Clarify security fixes shouldn't be previewed early on CI
2022-04-01 13:11:10 -05:00
Alex Crichton
3f9bff17c8 Support disabling backtraces at compile time (#3932)
* Support disabling backtraces at compile time

This commit adds support to Wasmtime to disable, at compile time, the
gathering of backtraces on traps. The `wasmtime` crate now sports a
`wasm-backtrace` feature which, when disabled, will mean that backtraces
are never collected at compile time nor are unwinding tables inserted
into compiled objects.

The motivation for this commit stems from the fact that generating a
backtrace is quite a slow operation. Currently backtrace generation is
done with libunwind and `_Unwind_Backtrace` typically found in glibc or
other system libraries. When thousands of modules are loaded into the
same process though this means that the initial backtrace can take
nearly half a second and all subsequent backtraces can take upwards of
hundreds of milliseconds. Relative to all other operations in Wasmtime
this is extremely expensive at this time. In the future we'd like to
implement a more performant backtrace scheme but such an implementation
would require coordination with Cranelift and is a big chunk of work
that may take some time, so in the meantime if embedders don't need a
backtrace they can still use this option to disable backtraces at
compile time and avoid the performance pitfalls of collecting
backtraces.

In general I tried to originally make this a runtime configuration
option but ended up opting for a compile-time option because `Trap::new`
otherwise has no arguments and always captures a backtrace. By making
this a compile-time option it was possible to configure, statically, the
behavior of `Trap::new`. Additionally I also tried to minimize the
amount of `#[cfg]` necessary by largely only having it at the producer
and consumer sites.

Also a noteworthy restriction of this implementation is that if
backtrace support is disabled at compile time then reference types
support will be unconditionally disabled at runtime. With backtrace
support disabled there's no way to trace the stack of wasm frames which
means that GC can't happen given our current implementation.

* Always enable backtraces for the C API
2022-03-16 09:18:16 -05:00
wasmtime-publish
9137b4a50e Bump Wasmtime to 0.35.0 (#3885)
[automatically-tag-and-release-this-commit]

Co-authored-by: Wasmtime Publish <wasmtime-publish@users.noreply.github.com>
2022-03-07 15:18:34 -06:00
Nick Fitzgerald
bad9a35418 wasm-mutate fuzz targets (#3836)
* fuzzing: Add a custom mutator based on `wasm-mutate`

* fuzz: Add a version of the `compile` fuzz target that uses `wasm-mutate`

* Update `wasmparser` dependencies
2022-02-23 12:14:11 -08:00
Alex Crichton
bbd4a4a500 Enable copy-on-write heap initialization by default (#3825)
* Enable copy-on-write heap initialization by default

This commit enables the `Config::memfd` feature by default now that it's
been fuzzed for a few weeks on oss-fuzz, and will continue to be fuzzed
leading up to the next release of Wasmtime in early March. The
documentation of the `Config` option has been updated as well as adding
a CLI flag to disable the feature.

* Remove ubiquitous "memfd" terminology

Switch instead to forms of "memory image" or "cow" or some combination
thereof.

* Update new option names
2022-02-22 17:12:18 -06:00
Andrew Brown
c183e93b80 x64: enable VTune support by default (#3821)
* x64: enable VTune support by default

After significant work in the `ittapi-rs` crate, this dependency should
build without issue on Wasmtime's supported operating systems: Windows,
Linux, and macOS. The difference in the release binary is <20KB, so this
change makes `vtune` a default build feature. This change upgrades
`ittapi-rs` to v0.2.0 and updates the documentation.

* review: add configuration for defaults in more places

* review: remove OS conditional compilation, add architecture

* review: do not default vtune feature in wasmtime-jit
2022-02-22 08:32:09 -08:00
Alex Crichton
5cd97c054d Update memfd support with a runtime toggle (#3778)
This commit updates the `memfd` support in Wasmtime to have a runtime
toggle as to whether it's used or not. The compile-time feature gating
`memfd` support is now also re-enabled by default, but the new runtime
switch is still disabled-by-default.

Additionally this commit updates our fuzz oracle to turn on/off the
memfd flag to re-enable fuzzing with memfd on oss-fuzz.
2022-02-08 15:47:13 -06:00
wasmtime-publish
39b88e4e9e Release Wasmtime 0.34.0 (#3768)
* Bump Wasmtime to 0.34.0

[automatically-tag-and-release-this-commit]

* Add release notes for 0.34.0

* Update release date to today

Co-authored-by: Wasmtime Publish <wasmtime-publish@users.noreply.github.com>
Co-authored-by: Alex Crichton <alex@alexcrichton.com>
2022-02-07 19:16:26 -06:00
Chris Fallin
88b53b12aa Turn off memfd by default, at least for this upcoming release. (#3774)
Since memfd support just landed, and has had only ~0.5 weeks to bake
with fuzzing, we want to make release 0.34.0 of Wasmtime without it
enabled by default. This PR disables memfd by default; it can be enabled
by specifying the `memfd` feature for the `wasmtime` crate, or when
building the commandline binary.

We plan to explicitly add memfd-enabled fuzzing targets, let that go for
a while, then probably re-enable memfd in the subsequent release if no
issues come up.
2022-02-07 15:44:53 -06:00
Chris Fallin
2a24a0fbde Make memfd image creation lazy (on first instantiation).
As a followup to the recent memfd allocator work, this PR makes the
memfd image creation occur on the first instantiation, rather than
immediately when the `Module` is loaded.

This shaves off a potentially surprising cost spike that would have
otherwise occurred: prior to the memfd work, no allocator eagerly read
the module's initial heap state into RAM. The behavior should now more
closely resemble what happened before (and the improvements in overall
instantiation time and performance, as compared to either eager init
with pure-mmap memory or user-mode pagefault handling with uffd,
remain).
2022-02-03 12:46:34 -08:00
Nick Fitzgerald
605c79fd05 Merge pull request #3756 from alexcrichton/update-wasm-tools
Update wasm-tools crates
2022-02-03 11:19:55 -08:00
Alex Crichton
b647561c44 memfd: Some minor follow-ups (#3759)
* Tweak memfd-related features crates

This commit changes the `memfd` feature for the `wasmtime-cli` crate
from an always-on feature to a default-on feature which can be disabled
at compile time. Additionally the `pooling-allocator` feature is also
given similar treatment.

Additionally some documentation was added for the `memfd` feature on the
`wasmtime` crate.

* Don't store `Arc<T>` in `InstanceAllocationRequest`

Instead store `&Arc<T>` to avoid having the clone that lives in
`InstanceAllocationRequest` not actually going anywhere. Otherwise all
instance allocation requires an extra clone to create it for the request
and an extra decrement when the request goes away. Internally clones are
made as necessary when creating instances.

* Enable the pooling allocator by default for `wasmtime-cli`

While perhaps not the most useful option since the CLI doesn't have a
great way to take advantage of this it probably makes sense to at least
match the features of `wasmtime` itself.

* Fix some lints and issues

* More compile fixes
2022-02-03 09:17:04 -06:00
Alex Crichton
65486a0680 Update wasm-tools crates
Nothing major here, just a routine update with a few extra things to
handle here-and-there.
2022-02-02 09:50:08 -08:00
Chris Fallin
01e6bb81fb Review feedback. 2022-02-01 15:49:44 -08:00
Chris Fallin
0ff8f6ab20 Make build-config magic use memfd by default. 2022-01-31 22:39:20 -08:00