* Remove unnecessary into_iter/map
Forgotten from a previous refactoring, this variable was already of the
right type!
* Move `wasmtime_jit::Compiler` into `wasmtime`
This `Compiler` struct is mostly a historical artifact at this point and
wasn't necessarily pulling much weight any more. This organization also
doesn't lend itself super well to compiling out `cranelift` when the
`Compiler` here is used for both parallel iteration configuration
settings as well as compilation.
The movement into `wasmtime` is relatively small, with
`Module::build_artifacts` being the main function added here which is a
merging of the previous functions removed from the `wasmtime-jit` crate.
* Add a `cranelift` compile-time feature to `wasmtime`
This commit concludes the saga of refactoring Wasmtime and making
Cranelift an optional dependency by adding a new Cargo feature to the
`wasmtime` crate called `cranelift`, which is enabled by default.
This feature is implemented by having a new cfg for `wasmtime` itself,
`cfg(compiler)`, which is used wherever compilation is necessary. This
bubbles up to disable APIs such as `Module::new`, `Func::new`,
`Engine::precompile_module`, and a number of `Config` methods affecting
compiler configuration. Checks are added to CI that when built in this
mode Wasmtime continues to successfully build. It's hoped that although
this is effectively "sprinkle `#[cfg]` until things compile" this won't
be too too bad to maintain over time since it's also an use case we're
interested in supporting.
With `cranelift` disabled the only way to create a `Module` is with the
`Module::deserialize` method, which requires some form of precompiled
artifact.
Two consequences of this change are:
* `Module::serialize` is also disabled in this mode. The reason for this
is that serialized modules contain ISA/shared flags encoded in them
which were used to produce the compiled code. There's no storage for
this if compilation is disabled. This could probably be re-enabled in
the future if necessary, but it may not end up being all that necessary.
* Deserialized modules are not checked to ensure that their ISA/shared
flags are compatible with the host CPU. This is actually already the
case, though, with normal modules. We'll likely want to fix this in
the future using a shared implementation for both these locations.
Documentation should be updated to indicate that `cranelift` can be
disabled, although it's not really the most prominent documentation
because this is expected to be a somewhat niche use case (albeit
important, just not too common).
* Always enable cranelift for the C API
* Fix doc example builds
* Fix check tests on GitHub Actions
* Reimplement how unwind information is stored
This commit is a major refactoring of how unwind information is stored
after compilation of a function has finished. Previously we would store
the raw `UnwindInfo` as a result of compilation and this would get
serialized/deserialized alongside the rest of the ELF object that
compilation creates. Whenever functions were registered with
`CodeMemory` this would also result in registering unwinding information
dynamically at runtime, which in the case of Unix, for example, would
dynamically created FDE/CIE entries on-the-fly.
Eventually I'd like to support compiling Wasmtime without Cranelift, but
this means that `UnwindInfo` wouldn't be easily available to decode into
and create unwinding information from. To solve this I've changed the
ELF object created to have the unwinding information encoded into it
ahead-of-time so loading code into memory no longer needs to create
unwinding tables. This change has two different implementations for
Windows/Unix:
* On Windows the implementation was much easier. The unwinding
information on Windows is already stored after the function itself in
the text section. This was actually slightly duplicated in object
building and in code memory allocation. Now the object building
continues to do the same, recording unwinding information after
functions, and code memory no longer manually tracks this.
Additionally Wasmtime will emit a special custom section in the object
file with unwinding information which is the list of
`RUNTIME_FUNCTION` structures that `RtlAddFunctionTable` expects. This
means that the object file has all the information precompiled into it
and registration at runtime is simply passing a few pointers around to
the runtime.
* Unix was a little bit more difficult than Windows. Today a `.eh_frame`
section is created on-the-fly with offsets in FDEs specified as the
absolute address that functions are loaded at. This absolute
address hindered the ability to precompile the FDE into the object
file itself. I've switched how addresses are encoded, though, to using
`DW_EH_PE_pcrel` which means that FDE addresses are now specified
relative to the FDE itself. This means that we can maintain a fixed
offset between the `.eh_frame` loaded in memory and the beginning of
code memory. When doing so this enables precompiling the `.eh_frame`
section into the object file and at runtime when loading an object no
further construction of unwinding information is needed.
The overall result of this commit is that unwinding information is no
longer stored in its cranelift-data-structure form on disk. This means
that this unwinding information format is only present during
compilation, which will make it that much easier to compile out
cranelift in the future.
This commit also significantly refactors `CodeMemory` since the way
unwinding information is handled is not much different from before.
Previously `CodeMemory` was suitable for incrementally adding more and
more functions to it, but nowadays a `CodeMemory` either lives per
module (in which case all functions are known up front) or it's created
once-per-`Func::new` with two trampolines. In both cases we know all
functions up front so the functionality of incrementally adding more and
more segments is no longer needed. This commit removes the ability to
add a function-at-a-time in `CodeMemory` and instead it can now only
load objects in their entirety. A small helper function is added to
build a small object file for trampolines in `Func::new` to handle
allocation there.
Finally, this commit also folds the `wasmtime-obj` crate directly into
the `wasmtime-cranelift` crate and its builder structure to be more
amenable to this strategy of managing unwinding tables.
It is not intentional to have any real functional change as a result of
this commit. This might accelerate loading a module from cache slightly
since less work is needed to manage the unwinding information, but
that's just a side benefit from the main goal of this commit which is to
remove the dependence on cranelift unwinding information being available
at runtime.
* Remove isa reexport from wasmtime-environ
* Trim down reexports of `cranelift-codegen`
Remove everything non-essential so that only the bits which will need to
be refactored out of cranelift remain.
* Fix debug tests
* Review comments
This commit started off by deleting the `cranelift_codegen::settings`
reexport in the `wasmtime-environ` crate and then basically played
whack-a-mole until everything compiled again. The main result of this is
that the `wasmtime-*` family of crates have generally less of a
dependency on the `TargetIsa` trait and type from Cranelift. While the
dependency isn't entirely severed yet this is at least a significant
start.
This commit is intended to be largely refactorings, no functional
changes are intended here. The refactorings are:
* A `CompilerBuilder` trait has been added to `wasmtime_environ` which
server as an abstraction used to create compilers and configure them
in a uniform fashion. The `wasmtime::Config` type now uses this
instead of cranelift-specific settings. The `wasmtime-jit` crate
exports the ability to create a compiler builder from a
`CompilationStrategy`, which only works for Cranelift right now. In a
cranelift-less build of Wasmtime this is expected to return a trait
object that fails all requests to compile.
* The `Compiler` trait in the `wasmtime_environ` crate has been souped
up with a number of methods that Wasmtime and other crates needed.
* The `wasmtime-debug` crate is now moved entirely behind the
`wasmtime-cranelift` crate.
* The `wasmtime-cranelift` crate is now only depended on by the
`wasmtime-jit` crate.
* Wasm types in `cranelift-wasm` no longer contain their IR type,
instead they only contain the `WasmType`. This is required to get
everything to align correctly but will also be required in a future
refactoring where the types used by `cranelift-wasm` will be extracted
to a separate crate.
* I moved around a fair bit of code in `wasmtime-cranelift`.
* Some gdb-specific jit-specific code has moved from `wasmtime-debug` to
`wasmtime-jit`.
* Move all trampoline compilation to `wasmtime-cranelift`
This commit moves compilation of all the trampolines used in wasmtime
behind the `Compiler` trait object to live in `wasmtime-cranelift`. The
long-term goal of this is to enable depending on cranelift *only* from
the `wasmtime-cranelift` crate, so by moving these dependencies we
should make that a little more flexible.
* Fix windows build
* Fully support multiple returns in Wasmtime
For quite some time now Wasmtime has "supported" multiple return values,
but only in the mose bare bones ways. Up until recently you couldn't get
a typed version of functions with multiple return values, and never have
you been able to use `Func::wrap` with functions that return multiple
values. Even recently where `Func::typed` can call functions that return
multiple values it uses a double-indirection by calling a trampoline
which calls the real function.
The underlying reason for this lack of support is that cranelift's ABI
for returning multiple values is not possible to write in Rust. For
example if a wasm function returns two `i32` values there is no Rust (or
C!) function you can write to correspond to that. This commit, however
fixes that.
This commit adds two new ABIs to Cranelift: `WasmtimeSystemV` and
`WasmtimeFastcall`. The intention is that these Wasmtime-specific ABIs
match their corresponding ABI (e.g. `SystemV` or `WindowsFastcall`) for
everything *except* how multiple values are returned. For multiple
return values we simply define our own version of the ABI which Wasmtime
implements, which is that for N return values the first is returned as
if the function only returned that and the latter N-1 return values are
returned via an out-ptr that's the last parameter to the function.
These custom ABIs provides the ability for Wasmtime to bind these in
Rust meaning that `Func::wrap` can now wrap functions that return
multiple values and `Func::typed` no longer uses trampolines when
calling functions that return multiple values. Although there's lots of
internal changes there's no actual changes in the API surface area of
Wasmtime, just a few more impls of more public traits which means that
more types are supported in more places!
Another change made with this PR is a consolidation of how the ABI of
each function in a wasm module is selected. The native `SystemV` ABI,
for example, is more efficient at returning multiple values than the
wasmtime version of the ABI (since more things are in more registers).
To continue to take advantage of this Wasmtime will now classify some
functions in a wasm module with the "fast" ABI. Only functions that are
not reachable externally from the module are classified with the fast
ABI (e.g. those not exported, used in tables, or used with `ref.func`).
This should enable purely internal functions of modules to have a faster
calling convention than those which might be exposed to Wasmtime itself.
Closes#1178
* Tweak some names and add docs
* "fix" lightbeam compile
* Fix TODO with dummy environ
* Unwind info is a property of the target, not the ABI
* Remove lightbeam unused imports
* Attempt to fix arm64
* Document new ABIs aren't stable
* Fix filetests to use the right target
* Don't always do 64-bit stores with cranelift
This was overwriting upper bits when 32-bit registers were being stored
into return values, so fix the code inline to do a sized store instead
of one-size-fits-all store.
* At least get tests passing on the old backend
* Fix a typo
* Add some filetests with mixed abi calls
* Get `multi` example working
* Fix doctests on old x86 backend
* Add a mixture of wasmtime/system_v tests
This commit is intended to do almost everything necessary for processing
the alias section of module linking. Most of this is internal
refactoring, the highlights being:
* Type contents are now stored separately from a `wasmtime_env::Module`.
Given that modules can freely alias types and have them used all over
the place, it seemed best to have one canonical location to type
storage which everywhere else points to (with indices). A new
`TypeTables` structure is produced during compilation which is shared
amongst all member modules in a wasm blob.
* Instantiation is heavily refactored to account for module linking. The
main gotcha here is that imports are now listed as "initializers". We
have a sort of pseudo-bytecode-interpreter which interprets the
initialization of a module. This is more complicated than just
matching imports at this point because in the module linking proposal
the module, alias, import, and instance sections may all be
interleaved. This means that imports aren't guaranteed to show up at
the beginning of the address space for modules/instances.
Otherwise most of the changes here largely fell out from these two
design points. Aliases are recorded as initializers in this scheme.
Copying around type information and/or just knowing type information
during compilation is also pretty easy since everything is just a
pointer into a `TypeTables` and we don't have to actually copy any types
themselves. Lots of various refactorings were necessary to accomodate
these changes.
Tests are hoped to cover a breadth of functionality here, but not
necessarily a depth. There's still one more piece of the module linking
proposal missing which is exporting instances/modules, which will come
in a future PR.
It's also worth nothing that there's one large TODO which isn't
implemented in this change that I plan on opening an issue for.
With module linking when a set of modules comes back from compilation
each modules has all the trampolines for the entire set of modules. This
is quite a lot of duplicate trampolines across module-linking modules.
We'll want to refactor this at some point to instead have only one set
of trampolines per set of module linking modules and have them shared
from there. I figured it was best to separate out this change, however,
since it's purely related to resource usage, and doesn't impact
non-module-linking modules at all.
cc #2094
* Provide filename/line number information in `Trap`
This commit extends the `Trap` type and `Store` to retain DWARF debug
information found in a wasm file unconditionally, if it's present. This
then enables us to print filenames and line numbers which point back to
actual source code when a trap backtrace is printed. Additionally the
`FrameInfo` type has been souped up to return filename/line number
information as well.
The implementation here is pretty simplistic currently. The meat of all
the work happens in `gimli` and `addr2line`, and otherwise wasmtime is
just schlepping around bytes of dwarf debuginfo here and there!
The general goal here is to assist with debugging when using wasmtime
because filenames and line numbers are generally orders of magnitude
better even when you already have a stack trace. Another nicety here is
that backtraces will display inlined frames (learned through debug
information), improving the experience in release mode as well.
An example of this is that with this file:
```rust
fn main() {
panic!("hello");
}
```
we get this stack trace:
```
$ rustc foo.rs --target wasm32-wasi -g
$ cargo run foo.wasm
Finished dev [unoptimized + debuginfo] target(s) in 0.16s
Running `target/debug/wasmtime foo.wasm`
thread 'main' panicked at 'hello', foo.rs:2:5
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
Error: failed to run main module `foo.wasm`
Caused by:
0: failed to invoke command default
1: wasm trap: unreachable
wasm backtrace:
0: 0x6c1c - panic_abort::__rust_start_panic::abort::h2d60298621b1ccbf
at /rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/panic_abort/src/lib.rs:77:17
- __rust_start_panic
at /rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/panic_abort/src/lib.rs:32:5
1: 0x68c7 - rust_panic
at /rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/std/src/panicking.rs:626:9
2: 0x65a1 - std::panicking::rust_panic_with_hook::h2345fb0909b53e12
at /rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/std/src/panicking.rs:596:5
3: 0x1436 - std::panicking::begin_panic::{{closure}}::h106f151a6db8c8fb
at /rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/std/src/panicking.rs:506:9
4: 0xda8 - std::sys_common::backtrace::__rust_end_short_backtrace::he55aa13f22782798
at /rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/std/src/sys_common/backtrace.rs:153:18
5: 0x1324 - std::panicking::begin_panic::h1727e7d1d719c76f
at /rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/std/src/panicking.rs:505:12
6: 0xfde - foo::main::h2db1313a64510850
at /Users/acrichton/code/wasmtime/foo.rs:2:5
7: 0x11d5 - core::ops::function::FnOnce::call_once::h20ee1cc04aeff1fc
at /rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/core/src/ops/function.rs:227:5
8: 0xddf - std::sys_common::backtrace::__rust_begin_short_backtrace::h054493e41e27e69c
at /rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/std/src/sys_common/backtrace.rs:137:18
9: 0x1d5a - std::rt::lang_start::{{closure}}::hd83784448d3fcb42
at /rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/std/src/rt.rs:66:18
10: 0x69d8 - core::ops::function::impls::<impl core::ops::function::FnOnce<A> for &F>::call_once::h564d3dad35014917
at /rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/core/src/ops/function.rs:259:13
- std::panicking::try::do_call::hdca4832ace5a8603
at /rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/std/src/panicking.rs:381:40
- std::panicking::try::ha8624a1a6854b456
at /rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/std/src/panicking.rs:345:19
- std::panic::catch_unwind::h71421f57cf2bc688
at /rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/std/src/panic.rs:382:14
- std::rt::lang_start_internal::h260050c92cd470af
at /rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/std/src/rt.rs:51:25
11: 0x1d0c - std::rt::lang_start::h0b4bcf3c5e498224
at /rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/std/src/rt.rs:65:5
12: 0xffc - <unknown>!__original_main
13: 0x393 - __muloti4
at /cargo/registry/src/github.com-1ecc6299db9ec823/compiler_builtins-0.1.35/src/macros.rs:269
```
This is relatively noisy by default but there's filenames and line
numbers! Additionally frame 10 can be seen to have lots of frames
inlined into it. All information is always available to the embedder but
we could try to handle the `__rust_begin_short_backtrace` and
`__rust_end_short_backtrace` markers to trim the backtrace by default as
well.
The only gotcha here is that it looks like `__muloti4` is out of place.
That's because the libc that Rust ships with doesn't have dwarf
information, although I'm not sure why we land in that function for
symbolizing it...
* Add a configuration switch for debuginfo
* Control debuginfo by default with `WASM_BACKTRACE_DETAILS`
* Try cpp_demangle on demangling as well
* Rename to WASMTIME_BACKTRACE_DETAILS
This commit removes the global variable associated with wasm traps which
stores frame information. The only purpose of this global is to help
symbolicate `Trap`s created since we support creating a `Trap` without a
`Store`. The global, however, is only used for wasm frames on the stack,
and when wasm frames are on the stack we know that our thread local for
"what was the last context" is set and configured.
The change here is to hijack this thread-local some more to effectively
store the `Store` inside of it. All frame information is then moved
directly into `Store` and no longer lives off on the side in a global.
Additionally support for registering/unregistering modules is now
simplified because once a module is registered with a store it can never
be unregistered.
This has one slight functional change where if there are two instances
of `Store` interleaving calls to wasm code on the stack we'll only be
able to symbolicate one of them instead of both. That's arguably also a
feature however because this is sort of a way to leak information across
stores right now.
Otherwise, though, this isn't intended to change any existing logic, but
instead keep everything working as-is.
This commit is intended to be the first of many in implementing the
module linking proposal. At this time this builds on #2059 so it
shouldn't land yet. The goal of this commit is to compile bare-bones
modules which use module linking, e.g. those with nested modules.
My hope with module linking is that almost everything in wasmtime only
needs mild refactorings to handle it. The goal is that all per-module
structures are still per-module and at the top level there's just a
`Vec` containing a bunch of modules. That's implemented currently where
`wasmtime::Module` contains `Arc<[CompiledModule]>` and an index of
which one it's pointing to. This should enable
serialization/deserialization of any module in a nested modules
scenario, no matter how you got it.
Tons of features of the module linking proposal are missing from this
commit. For example instantiation flat out doesn't work, nor does
import/export of modules or instances. That'll be coming as future
commits, but the purpose here is to start laying groundwork in Wasmtime
for handling lots of modules in lots of places.
This commit removes all import resolution handling from the
`wasmtime-jit` crate, instead moving the logic to the `wasmtime` crate.
Previously `wasmtime-jit` had a generic `Resolver` trait and would do
all the import type matching itself, but with the upcoming
module-linking implementation this is going to get much trickier.
The goal of this commit is to centralize all meaty "preparation" logic
for instantiation into one location, probably the `wasmtime` crate
itself. Instantiation will soon involve recursive instantiation and
management of alias definitions as well. Having everything in one
location, especially with access to `Store` so we can persist
instances for safety, will be quite convenient.
Additionally the `Resolver` trait isn't really necessary any more since
imports are, at the lowest level, provided as a list rather than a map
of some kind. More generic resolution functionality is provided via
`Linker` or user layers on top of `Instance::new` itself. This makes
matching up provided items to expected imports much easier as well.
Overall this is largely just moving code around, but most of the code
in the previous `resolve_imports` phase can be deleted since a lot of it
is handled by surrounding pieces of `wasmtime` as well.
- Create the ELF image from Compilation
- Create CodeMemory from the ELF image
- Link using ELF image
- Remove creation of GDB JIT images from crates/debug
- Move make_trampoline from compiler.rs
This commit fixes an issue where the global registration of frame data
goes away once the `wasmtime::Module` has been dropped. Even after this
has been dropped, though, there may still be `wasmtime::Func` instances
which reference the original module, so it's only once the underlying
`wasmtime_runtime::Instance` has gone away that we can drop everything.
Closes#1479
This commit makes the following changes to unwind information generation in
Cranelift:
* Remove frame layout change implementation in favor of processing the prologue
and epilogue instructions when unwind information is requested. This also
means this work is no longer performed for Windows, which didn't utilize it.
It also helps simplify the prologue and epilogue generation code.
* Remove the unwind sink implementation that required each unwind information
to be represented in final form. For FDEs, this meant writing a
complete frame table per function, which wastes 20 bytes or so for each
function with duplicate CIEs. This also enables Cranelift users to collect the
unwind information and write it as a single frame table.
* For System V calling convention, the unwind information is no longer stored
in code memory (it's only a requirement for Windows ABI to do so). This allows
for more compact code memory for modules with a lot of functions.
* Deletes some duplicate code relating to frame table generation. Users can
now simply use gimli to create a frame table from each function's unwind
information.
Fixes#1181.
* wasmtime: Pass around more contexts instead of fields
This commit refactors some wasmtime internals to pass around more
context-style structures rather than individual fields of each
structure. The intention here is to make the addition of fields to a
structure easier to plumb throughout the internals of wasmtime.
Currently you need to edit lots of functions to pass lots of parameters,
but ideally after this you'll only need to edit one or two struct fields
and then relevant locations have access to the information already.
Updates in this commit are:
* `debug_info` configuration is now folded into `Tunables`. Additionally
a `wasmtime::Config` now holds a `Tunables` directly and is passed
into an internal `Compiler`. Eventually this should allow for direct
configuration of the `Tunables` attributes from the `wasmtime` API,
but no new configuration is exposed at this time.
* `ModuleTranslation` is now passed around as a whole rather than
passing individual components to allow access to all the fields,
including `Tunables`.
This was motivated by investigating what it would take to optionally
allow loops and such to get interrupted, but that sort of codegen
setting was currently relatively difficult to plumb all the way through
and now it's hoped to be largely just an addition to `Tunables`.
* Fix lightbeam compile
* Handle select relocations while generating trampolines
Trampoline generation for all function signatures exposed a preexisting
bug in wasmtime where trampoline generation occasionally does have
relocations, but it's asserted that trampolines don't generate
relocations, causing a panic. The relocation is currently primarily the
probestack function which happens when functions might have a huge
number of parameters, but not so huge as to blow the wasmparser limit of
how many parameters are allowed.
This commit fixes the issue by handling relocations for trampolines in
the same manner as the rest of the code. Note that dynamically-generated
trampolines via the `Func` API still panic if they have too many
arguments and generate a relocation, but it seems like we can try to fix
that later if the need truly arises.
Closes#1322
* Log trampoline relocations
* Refactor wasmtime_runtime::Export
Instead of an enumeration with variants that have data fields have an
enumeration where each variant has a struct, and each struct has the
data fields. This allows us to store the structs in the `wasmtime` API
and avoid lots of `panic!` calls and various extraneous matches.
* Pre-generate trampoline functions
The `wasmtime` crate supports calling arbitrary function signatures in
wasm code, and to do this it generates "trampoline functions" which have
a known ABI that then internally convert to a particular signature's ABI
and call it. These trampoline functions are currently generated
on-the-fly and are cached in the global `Store` structure. This,
however, is suboptimal for a few reasons:
* Due to how code memory is managed each trampoline resides in its own
64kb allocation of memory. This means if you have N trampolines you're
using N * 64kb of memory, which is quite a lot of overhead!
* Trampolines are never free'd, even if the referencing module goes
away. This is similar to #925.
* Trampolines are a source of shared state which prevents `Store` from
being easily thread safe.
This commit refactors how trampolines are managed inside of the
`wasmtime` crate and jit/runtime internals. All trampolines are now
allocated in the same pass of `CodeMemory` that the main module is
allocated into. A trampoline is generated per-signature in a module as
well, instead of per-function. This cache of trampolines is stored
directly inside of an `Instance`. Trampolines are stored based on
`VMSharedSignatureIndex` so they can be looked up from the internals of
the `ExportFunction` value.
The `Func` API has been updated with various bits and pieces to ensure
the right trampolines are registered in the right places. Overall this
should ensure that all trampolines necessary are generated up-front
rather than lazily. This allows us to remove the trampoline cache from
the `Compiler` type, and move one step closer to making `Compiler`
threadsafe for usage across multiple threads.
Note that as one small caveat the `Func::wrap*` family of functions
don't need to generate a trampoline at runtime, they actually generate
the trampoline at compile time which gets passed in.
Also in addition to shuffling a lot of code around this fixes one minor
bug found in `code_memory.rs`, where `self.position` was loaded before
allocation, but the allocation may push a new chunk which would cause
`self.position` to be zero instead.
* Pass the `SignatureRegistry` as an argument to where it's needed.
This avoids the need for storing it in an `Arc`.
* Ignore tramoplines for functions with lots of arguments
Co-authored-by: Dan Gohman <sunfish@mozilla.com>
* 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
* Move compilation into Module from Instance.
* Fix fuzzing
* Use wasmtime::Module in fuzzing crates
Instead of wasmtime_jit.
* Compile eagerly.
* Review fixes.
* Always use the saved name.
* Preserve the former behavior for fuzzing oracle
* Migrate back to `std::` stylistically
This commit moves away from idioms such as `alloc::` and `core::` as
imports of standard data structures and types. Instead it migrates all
crates to uniformly use `std::` for importing standard data structures
and types. This also removes the `std` and `core` features from all
crates to and removes any conditional checking for `feature = "std"`
All of this support was previously added in #407 in an effort to make
wasmtime/cranelift "`no_std` compatible". Unfortunately though this
change comes at a cost:
* The usage of `alloc` and `core` isn't idiomatic. Especially trying to
dual between types like `HashMap` from `std` as well as from
`hashbrown` causes imports to be surprising in some cases.
* Unfortunately there was no CI check that crates were `no_std`, so none
of them actually were. Many crates still imported from `std` or
depended on crates that used `std`.
It's important to note, however, that **this does not mean that wasmtime
will not run in embedded environments**. The style of the code today and
idioms aren't ready in Rust to support this degree of multiplexing and
makes it somewhat difficult to keep up with the style of `wasmtime`.
Instead it's intended that embedded runtime support will be added as
necessary. Currently only `std` is necessary to build `wasmtime`, and
platforms that natively need to execute `wasmtime` will need to use a
Rust target that supports `std`. Note though that not all of `std` needs
to be supported, but instead much of it could be configured off to
return errors, and `wasmtime` would be configured to gracefully handle
errors.
The goal of this PR is to move `wasmtime` back to idiomatic usage of
features/`std`/imports/etc and help development in the short-term.
Long-term when platform concerns arise (if any) they can be addressed by
moving back to `no_std` crates (but fixing the issues mentioned above)
or ensuring that the target in Rust has `std` available.
* Start filling out platform support doc
