* Fix a possible use-after-free with `Global`
This commit fixes an issue with the implementation of the
`wasmtime::Global` type where if it previously outlived the original
`Instance` it came from then you could run into a use-after-free. Now
the `Global` type holds onto its underlying `InstanceHandle` to ensure
it retains ownership of the underlying backing store of the global's
memory.
* rustfmt
Previously `Instance` was always allocated with `mmap`. This was done to
future-proof `Instance` for allowing storing the memory itself inline
with an `Instance` allocation, but this can actually be done with
`alloc`/`dealloc` since they take an alignment. By using `malloc`/`free`
we can avoid fragmentation as well as hook into standard leak tracking
mechanisms.
* Generate trampolines based on signatures
Instead of generating a trampoline-per-function generate a
trampoline-per-signature. This should hopefully greatly increase the
cache hit rate on trampolines within a module and avoid generating a
function-per-function.
* Update crates/runtime/src/traphandlers.rs
Co-Authored-By: Sergei Pepyakin <s.pepyakin@gmail.com>
Co-authored-by: Sergei Pepyakin <s.pepyakin@gmail.com>
* Update cranelift to 0.58.0
* Update `wasmprinter` dep to require 0.2.1
We already had it in the lock file, but this ensures we won't ever go back down.
* Ensure that our error messages match `assert_invalid`'s
The bulk of this work was done in
https://github.com/bytecodealliance/wasmparser/pull/186 but now we can test it
at the `wasmtime` level as well.
Fixes#492
* Stop feeling guilty about not matching `assert_malformed` messages
Remove the "TODO" and stop printing warning messages. These would just be busy
work to implement, and getting all the messages the exact same relies on using
the same structure as the spec interpreter's parser, which means that where you
have a helper function and they don't, then things go wrong, and vice versa. Not
worth it.
Fixes#492
* Enable (but ignore) the reference-types proposal tests
* Match test suite directly, instead of roundabout starts/endswith
* Enable (but ignore) bulk memory operations proposal test suite
* Add some debug logging to fuzzers
This is useful when trying to figure out what happened locally when
debugging fuzz test cases. By setting `RUST_LOG=wasmtime_fuzzing=debug`
you can get wasm files written to disk and for the API calls test case
see what API calls are being made.
* Also write out `*.wat` files
* rustfmt
* Remove return value from `log_wasm`
* Remove unused import
* Remove the `action` and `context` modules from `wasmtime_jit`
These modules are now no longer necessary with the `wasmtime` crate
fleshed out, and they're entirely subsumed by the `wasmtime` API as
well.
* Remove some more modules
* Remove the `jit_function_registry` global state
This commit removes on the final pieces of global state in wasmtime
today, the `jit_function_registry` module. The purpose of this module is
to help translate a native backtrace with native program counters into a
wasm backtrace with module names, function names, and wasm module
indices. To that end this module retained a global map of function
ranges to this metadata information for each compiled function.
It turns out that we already had a `NAMES` global in the `wasmtime`
crate for symbolicating backtrace addresses, so this commit moves that
global into its own file and restructures the internals to account for
program counter ranges as well. The general set of changes here are:
* Remove `jit_function_registry`
* Remove `NAMES`
* Create a new `frame_info` module which has a singleton global
registering compiled module's frame information.
* Update traps to use the `frame_info` module to symbolicate pcs,
directly extracting a `FrameInfo` from the module.
* Register and unregister information on a module level instead of on a
per-function level (at least in terms of locking granluarity).
This commit leaves the new `FRAME_INFO` global variable as the only
remaining "critical" global variable in `wasmtime`, which only exists
due to the API of `Trap` where it doesn't take in any extra context when
capturing a stack trace through which we could hang off frame
information. I'm thinking though that this is ok, and we can always
tweak the API of `Trap` in the future if necessary if we truly need to
accomodate this.
* Remove a lazy_static dep
* Add some comments and restructure
* Add more CLI flags for wasm features
This commit adds a few more flags to enable wasm features via the CLI,
mirroring the existing `--enable-simd` flag:
* `--enable-reference-types`
* `--enable-multi-value`
* `--enable-threads`
* `--enable-bulk-memory`
Additionally the bulk memory feature is now automatically enabled if
`reference-types` or `threads` are enabled since those two proposals
largely depend on `bulk-memory`.
* Add --enable-all to enable all wasm features
* Update src/lib.rs
Co-Authored-By: Peter Huene <peterhuene@protonmail.com>
* Apply suggestions from code review
Co-Authored-By: Peter Huene <peterhuene@protonmail.com>
Co-authored-by: Peter Huene <peterhuene@protonmail.com>
* Fuzz the multi-value support
This commit enables multi-value by default for the fuzzers, in theory
allowing us to find panics and such in the multi-value implementation.
Or even runtime errors through the differential fuzzing!
* Don't fuzz differential on multi value
There's not really much reason to amortize the cost of this mtime
calculation here since it's only done with debug assertions anyway, so
let's avoid an extra dependency and just have a function do it inline.
* Remove all global state from the caching system
This commit is a continuation of an effort to remove usages of
`lazy_static!` and similar global state macros which can otherwise be
accomodated with passing objects around. Previously there was a global
cache system initialized per-process, but it was initialized in a bit of
a roundabout way and wasn't actually reachable from the `wasmtime` crate
itself. The changes here remove all global state, refactor many of the
internals in the cache system, and makes configuration possible through
the `wasmtime` crate.
Specifically some changes here are:
* Usage of `lazy_static!` and many `static` items in the cache module
have all been removed.
* Global `cache_config()`, `worker()`, and `init()` functions have all
been removed. Instead a `CacheConfig` is a "root object" which
internally owns its worker and passing around the `CacheConfig` is
required for cache usage.
* The `wasmtime::Config` structure has grown options to load and parse
cache files at runtime. Currently only loading files is supported,
although we can likely eventually support programmatically configuring
APIs as well.
* Usage of the `spin` crate has been removed and the dependency is removed.
* The internal `errors` field of `CacheConfig` is removed, instead
changing all relevant methods to return a `Result<()>` instead of
storing errors internally.
* Tests have all been updated with the new interfaces and APIs.
Functionally no real change is intended here. Usage of the `wasmtime`
CLI, for example, should still enable the cache by default.
* Fix lightbeam compilation
* Remove global state for trap registration
There's a number of changes brought about in this commit, motivated by a
few things. One motivation was to remove an instance of using
`lazy_static!` in an effort to remove global state and encapsulate it
wherever possible. A second motivation came when investigating a
slowly-compiling wasm module (a bit too slowly) where a good chunk of
time was spent in managing trap registrations.
The specific change made here is that `TrapRegistry` is now stored
inside of a `Compiler` instead of inside a global. Additionally traps
are "bulk registered" for a module rather than one-by-one. This form of
bulk-registration allows optimizing the locks used here, where a lock is
only held for a module at-a-time instead of once-per-function.
With these changes the "unregister" logic has also been tweaked a bit
here and there to continue to work. As a nice side effect the `Compiler`
type now has one fewer field that requires actual mutability and has
been updated for multi-threaded compilation, nudging us closer to a
world where we can support multi-threaded compilation. Yay!
In terms of performance improvements, a local wasm test file that
previously took 3 seconds to compile is now 10% faster to compile,
taking ~2.7 seconds now.
* Perform trap resolution after unwinding
This avoids taking locks in signal handlers which feels a bit iffy...
* Remove `TrapRegistration::dummy()`
Avoid an case where you're trying to lookup trap information from a
dummy module for something that happened in a different module.
* Tweak some comments
The intention of the `wasmtime` crate was to disable this verifier by
default, but it looks like cranelift actually has it turned on by
default which was making our documentation incorrect!
This was discovered by seeing a number of timeouts when fuzzing. The
debug verifier is great for fuzzing, however, so fuzzing is updated to
enable this unconditionally, meaning we'll still have timeouts. For
general users though this should make the documentation correct that the
`wasmtime` crate, by default, disables the debug verifier.
Investigating a susprisingly slow-compiling module recently, it turns
out that if you create a wasm module with 40k empty functions (e.g.
`(module (func) (func) (func) ...)`) then it takes **3 seconds** to
compile and drop via the CLI locally on a Linux system. This seems like
an extraordinary amount of time for "doing nothing", and after some
profiling I found that basically all of the time was spent in
`__deregister_frame` calls.
Poking around in the source it looks like libgcc is managing some form
of linked list, and by deregistering in the LIFO order instead of FIFO
order it avoids a quadratic search of all registered functions. Now that
being said it's still pretty bad to do a linear search all the time, and
nothing will be fixed if there are *two* instances both with 40k
functions.
For now though I hope that this will patch over the performance issue
and we can figure out better ways to manage this in the future.
* Reimplement `wasmtime-wasi` on top of `wasmtime`
This commit reimplements the `wasmtime-wasi` crate on top of the
`wasmtime` API crate, instead of being placed on top of the `wasmtime-*`
family of internal crates. The purpose here is to continue to exercise
the API as well as avoid usage of internals wherever possible and
instead use the safe API as much as possible.
The `wasmtime-wasi` crate's API has been updated as part of this PR as
well. The general outline of it is now:
* Each module snapshot has a `WasiCtxBuilder`, `WasiCtx`, and `Wasi`
type.
* The `WasiCtx*` types are reexported from `wasi-common`.
* The `Wasi` type is synthesized by the `wig` crate's procedural macro
* The `Wasi` type exposes one constructor which takes a `Store` and a
`WasiCtx`, and produces a `Wasi`
* Each `Wasi` struct fields for all the exported functions in that wasi
module. They're all public an they all have type `wasmtime::Func`
* The `Wasi` type has a `get_export` method to fetch an struct field by
name.
The intention here is that we can continue to make progress on #727 by
integrating WASI construction into the `Instance::new` experience, but
it requires everything to be part of the same system!
The main oddity required by the `wasmtime-wasi` crate is that it needs
access to the caller's `memory` export, if any. This is currently done
with a bit of a hack and is expected to go away once interface types are
more fully baked in.
* Remove now no-longer-necessary APIs from `wasmtime`
* rustfmt
* Rename to from_abi
* Move `Func` to its own file
* Support `Func` imports with zero shims
This commit extends the `Func` type in the `wasmtime` crate with static
`wrap*` constructors. The goal of these constructors is to create a
`Func` type which has zero shims associated with it, creating as small
of a layer as possible between wasm code and calling imported Rust code.
This is achieved by creating an `extern "C"` shim function which matches
the ABI of what Cranelift will generate, and then the host function is
passed directly into an `InstanceHandle` to get called later. This also
enables enough inlining opportunities that LLVM will be able to see all
functions and inline everything to the point where your function is
called immediately from wasm, no questions asked.
Whenever we enter wasm code we need to verify that the correct number
and the correct types of arguments were passed in, lest we misinterpret
bits!
Closes#52
* Remove another thread local in `instance.rs`
This commit removes another usage of `thread_local!` in the continued
effort to centralize all thread-local state per-call (or basically state
needed for traps) in one location. This removal is targeted at the
support for custom signal handlers on instances, removing the previous
stack of instances with instead a linked list of instances.
The `with_signals_on` method is no longer necessary (since it was always
called anyway) and is inferred from the first `vmctx` argument of the
entrypoints into wasm. These functions establish a linked list of
instances on the stack, if needed, to handle signals when they happen.
This involved some refactoring where some C++ glue was moved into Rust,
so now Rust handles a bit more of the signal handling logic.
* Update some inline docs about `HandleTrap`
During creation of an `InstanceHandle` if a link error occurred (such as
an element segment doesn't fit) then the instance itself would be leaked
by accident. This commit fixes the issue by ensuring that an
`InstanceHandle` is created very quickly so if any initialization later
fails it will be cleaned up through normal destructors.
* Improve panics/traps from imported functions
This commit performs a few refactorings and fixes a bug as well. The
changes here are:
* The `thread_local!` in the `wasmtime` crate for trap information is
removed. The thread local in the `wasmtime_runtime` crate is now
leveraged to transmit trap information.
* Panics in user-provided functions are now caught explicitly to be
carried across JIT code manually. Getting Rust panics unwinding
through JIT code is pretty likely to be super tricky and difficult to
do, so in the meantime we can get by with catching panics and resuming
the panic once we've resumed in Rust code.
* Various take/record trap apis have all been removed in favor of
working directly with `Trap` objects, where the internal trap object
has been expanded slightly to encompass user-provided errors as well.
This borrows a bit #839 and otherwise will...
Closes#848
* Rename `r#return` to `ret`