10 Commits

Author SHA1 Message Date
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
bc8e36a6af Refactor and optimize the flat type calculations (#4708)
* Optimize flat type representation calculations

Previously calculating the flat type representation would be done
recursively for an entire type tree every time it was visited.
Additionally the flat type representation was entirely built only to be
thrown away if it was too large at the end. This chiefly presented a
source of recursion based on the type structure in the component model
which fuzzing does not like as it reports stack overflows.

This commit overhauls the representation of flat types in Wasmtime by
caching the representation for each type in the compile-time
`ComponentTypesBuilder` structure. This avoids recalculating each time
the flat representation is queried and additionally allows opportunity
to have more short-circuiting to avoid building overly-large vectors.

* Remove duplicate flat count calculation in wasmtime

Roughly share the infrastructure in the `wasmtime-environ` crate, namely
the non-recursive and memoizing nature of the calculation.

* Fix component fuzz build

* Fix example compile
2022-08-16 13:31:47 -05:00
Alex Crichton
bd70dbebbd Deduplicate some size/align calculations (#4658)
This commit is an effort to reduce the amount of complexity around
managing the size/alignment calculations of types in the canonical ABI.
Previously the logic for the size/alignment of a type was spread out
across a number of locations. While each individual calculation is not
really the most complicated thing in the world having the duplication in
so many places was constantly worrying me.

I've opted in this commit to centralize all of this within the runtime
at least, and now there's only one "duplicate" of this information in
the fuzzing infrastructure which is to some degree less important to
deduplicate. This commit introduces a new `CanonicalAbiInfo` type to
house all abi size/align information for both memory32 and memory64.
This new type is then used pervasively throughout fused adapter
compilation, dynamic `Val` management, and typed functions. This type
was also able to reduce the complexity of the macro-generated code
meaning that even `wasmtime-component-macro` is performing less math
than it was before.

One other major feature of this commit is that this ABI information is
now saved within a `ComponentTypes` structure. This avoids recursive
querying of size/align information frequently and instead effectively
caching it. This was a worry I had for the fused adapter compiler which
frequently sought out size/align information and would recursively
descend each type tree each time. The `fact-valid-module` fuzzer is now
nearly 10x faster in terms of iterations/s which I suspect is due to
this caching.
2022-08-09 14:52:20 -05:00
Alex Crichton
866ec46613 Implement roundtrip fuzzing of component adapters (#4640)
* Improve the `component_api` fuzzer on a few dimensions

* Update the generated component to use an adapter module. This involves
  two core wasm instances communicating with each other to test that
  data flows through everything correctly. The intention here is to fuzz
  the fused adapter compiler. String encoding options have been plumbed
  here to exercise differences in string encodings.

* Use `Cow<'static, ...>` and `static` declarations for each static test
  case to try to cut down on rustc codegen time.

* Add `Copy` to derivation of fuzzed enums to make `derive(Clone)`
  smaller.

* Use `Store<Box<dyn Any>>` to try to cut down on codegen by
  monomorphizing fewer `Store<T>` implementation.

* Add debug logging to print out what's flowing in and what's flowing
  out for debugging failures.

* Improve `Debug` representation of dynamic value types to more closely
  match their Rust counterparts.

* Fix a variant issue with adapter trampolines

Previously the offset of the payload was calculated as the discriminant
aligned up to the alignment of a singular case, but instead this needs
to be aligned up to the alignment of all cases to ensure all cases start
at the same location.

* Fix a copy/paste error when copying masked integers

A 32-bit load was actually doing a 16-bit load by accident since it was
copied from the 16-bit load-and-mask case.

* Fix f32/i64 conversions in adapter modules

The adapter previously erroneously converted the f32 to f64 and then to
i64, where instead it should go from f32 to i32 to i64.

* Fix zero-sized flags in adapter modules

This commit corrects the size calculation for zero-sized flags in
adapter modules.

cc #4592

* Fix a variant size calculation bug in adapters

This fixes the same issue found with variants during normal host-side
fuzzing earlier where the size of a variant needs to align up the
summation of the discriminant and the maximum case size.

* Implement memory growth in libc bump realloc

Some fuzz-generated test cases are copying lists large enough to exceed
one page of memory so bake in a `memory.grow` to the bump allocator as
well.

* Avoid adapters of exponential size

This commit is an attempt to avoid adapters being exponentially sized
with respect to the type hierarchy of the input. Previously all
adaptation was done inline within each adapter which meant that if
something was structured as `tuple<T, T, T, T, ...>` the translation of
`T` would be inlined N times. For very deeply nested types this can
quickly create an exponentially sized adapter with types of the form:

    (type $t0 (list u8))
    (type $t1 (tuple $t0 $t0))
    (type $t2 (tuple $t1 $t1))
    (type $t3 (tuple $t2 $t2))
    ;; ...

where the translation of `t4` has 8 different copies of translating
`t0`.

This commit changes the translation of types through memory to almost
always go through a helper function. The hope here is that it doesn't
lose too much performance because types already reside in memory.

This can still lead to exponentially sized adapter modules to a lesser
degree where if the translation all happens on the "stack", e.g. via
`variant`s and their flat representation then many copies of one
translation could still be made. For now this commit at least gets the
problem under control for fuzzing where fuzzing doesn't trivially find
type hierarchies that take over a minute to codegen the adapter module.

One of the main tricky parts of this implementation is that when a
function is generated the index that it will be placed at in the final
module is not known at that time. To solve this the encoded form of the
`Call` instruction is saved in a relocation-style format where the
`Call` isn't encoded but instead saved into a different area for
encoding later. When the entire adapter module is encoded to wasm these
pseudo-`Call` instructions are encoded as real instructions at that
time.

* Fix some memory64 issues with string encodings

Introduced just before #4623 I had a few mistakes related to 64-bit
memories and mixing 32/64-bit memories.

* Actually insert into the `translate_mem_funcs` map

This... was the whole point of having the map!

* Assert memory growth succeeds in bump allocator
2022-08-08 18:01:45 +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
Joel Dice
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>
2022-08-04 12:02:55 -05:00
Alex Crichton
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.
2022-08-01 16:05:09 +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