Replace setjmp/longjmp usage in Wasmtime (#11592)

Since Wasmtime's inception it's used the `setjmp` and `longjmp`
functions in C to implement handling of traps. While this solution was
easy to imple

Replace setjmp/longjmp usage in Wasmtime (#11592)

Since Wasmtime's inception it's used the `setjmp` and `longjmp`
functions in C to implement handling of traps. While this solution was
easy to implement, relatively portable, and performant enough, there are
a number of downsides that have evolved over time to make this an
unattractive approach in the long run:

* Using `setjmp` fundamentally requires using C because Rust does not
understand a function that returns twice. It's fundamentally unsound
to invoke `setjmp` in Rust meaning that Wasmtime has forever needed a
C compiler configured and set up to build. This notably means that
`cargo check` cannot check other targets easily.

* Using `longjmp` means that Rust function frames are unwound on the
stack without running destructors. This is a dangerous operation of
which we get no protection from the compiler about. Both frames
entering wasm and frames exiting wasm are all skipped. Absolutely
minimizing this has been beneficial for portability to platforms such
as Pulley.

* Currently the no_std implementation of Wasmtime requires embedders to
provide `wasmtime_{setjmp,longjmp}` which is a thorn in the side of
what is otherwise a mostly entirely independent implementation of
Wasmtime.

* There is a performance floor to using `setjmp` and `longjmp`. Calling
`setjmp` requires using C but Wasmtime is otherwise written in Rust
meaning that there's a Rust->C->Rust->Wasm boundary which
fundamentally can't be inlined without cross-language LTO which is
difficult to configure.

* With the implementation of the WebAssembly exceptions proposal
Wasmtime now has two means of unwinding the stack. Ideally Wasmtime
would only have one, and the more general one is the method of
exceptions.

* Jumping out of a signal handler on Unix is tricky business. While
we've made it work it's generally most robust of the signal handler
simply returns which it now does.

With all of that in mind the purpose of this commit is to replace the
setjmp/longjmp mechanism of handling traps with the recently implemented
support for exceptions in Cranelift. That is intended to resolve all of
the above points in one swoop.

One point in particular though that's nice about setjmp/longjmp is that
unwinding the stack on a trap is an O(1) operation. For situations such
as stack overflow that's a particularly nice property to have as we can
guarantee embedders that traps are a constant time (albeit somewhat
expensive with signals) operation. Exceptions naively require unwinding
the entire stack, and although frame pointers mean we're just traversing
a linked list I wanted to preserve the O(1) property here nonetheless.
To achieve this a solution is implemented where the array-to-wasm
(host-to-wasm) trampolines setup state in `VMStoreContext` so looking up
the current trap handler frame is an O(1) operation. Namely the sp/fp/pc
values for a `Handler` are stored inline.

Implementing this feature required supporting
relocations-to-offsets-in-functions which was not previously supported
by Wasmtime. This required Cranelift refactorings such as #11570, #11585,
and #11576. This then additionally required some more refactoring in
this commit which was difficult to split out as it otherwise wouldn't be
tested.

Apart from the relocation-related business much of this change is about
updating the platform signal handlers to use exceptions instead of
longjmp to return. For example on Unix this means updating the
`ucontext_t` with register values that the handler specifies. Windows
involves updating similar contexts, and macOS mach ports ended up not
needing too many changes.

In terms of overall performance the relevant benchmark from this
repository, compared to before this commit, is:

sync/no-hook/core - host-to-wasm - typed - nop
time: [10.552 ns 10.561 ns 10.571 ns]
change: [−7.5238% −7.4011% −7.2786%] (p = 0.00 < 0.05)
Performance has improved.

Closes #3927
cc #10923

prtest:full

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Modernize architecture documentation on linear memory (#10364)

The previous docs had fallen a bit behind the times.

Turn the `wasmtime-runtime` crate into the `wasmtime::runtime::vm` module (#8501)

* Expose `wasmtime-runtime` as `crate::runtime::vm` internally for the `wasmtime` crate

* Rewrite uses of `wasmtime

Turn the `wasmtime-runtime` crate into the `wasmtime::runtime::vm` module (#8501)

* Expose `wasmtime-runtime` as `crate::runtime::vm` internally for the `wasmtime` crate

* Rewrite uses of `wasmtime_runtime` to `crate::runtime::vm`

* Remove dep on `wasmtime-runtime` from `wasmtime-cli`

* Move the `wasmtime-runtime` crate into the `wasmtime::runtime::vm` module

* Update labeler for merged crates

* Fix `publish verify`

prtest:full

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Remove `wasmtime-jit` (#7769)

* Move `jit` crate to `environ`

Move the platform agnostic parts of the crate `wasmtime-jit` to
`wasmtime-environ`. This is the first part of the refactoring discussed

Remove `wasmtime-jit` (#7769)

* Move `jit` crate to `environ`

Move the platform agnostic parts of the crate `wasmtime-jit` to
`wasmtime-environ`. This is the first part of the refactoring discussed
here: https://github.com/bytecodealliance/wasmtime/issues/7652 and a
follow up will move the remaining parts of `wasmtime-jit` so that the
crate can be deleted.

* Move `jit` crate to `wasmtime`

Move the remaining parts of `wasmtime-jit` to the `wasmtime` crate and
remove `wasmtime-jit`. This is part of the refactoring discussed in
https://github.com/bytecodealliance/wasmtime/issues/7652.

* undo toml formatting

* Trigger pipeline: prtest:full

* Remove `jit` directory

* move `ProfilingAgent` out of `profiling` feature

* add links to ELF_NAME_DATA

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Correct grammar (#7224)

* Update cli-install.md

Correct grammar.

* Update contributing-architecture.md

Correct grammar.

Update notes about 64-bit memory support (#6868)

Closes #6865

Rename `VMCallerCheckedAnyfunc` to `VMCallerCheckedFuncRef` (#5738)

At some point what is now `funcref` was called `anyfunc` and the spec changed,
but we didn't update our internal names. This does

Rename `VMCallerCheckedAnyfunc` to `VMCallerCheckedFuncRef` (#5738)

At some point what is now `funcref` was called `anyfunc` and the spec changed,
but we didn't update our internal names. This does that.

Co-authored-by: Jamey Sharp <[email protected]>

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Chore fix typo in docs/contributing-architecture.md (#3449)

Remove the lightbeam backend (#3390)

This commit removes the Lightbeam backend from Wasmtime as per [RFC 14].
This backend hasn't received maintenance in quite some time, and as [RFC
14] indicates

Remove the lightbeam backend (#3390)

This commit removes the Lightbeam backend from Wasmtime as per [RFC 14].
This backend hasn't received maintenance in quite some time, and as [RFC
14] indicates this doesn't meet the threshold for keeping the code
in-tree, so this commit removes it.

A fast "baseline" compiler may still be added in the future. The
addition of such a backend should be in line with [RFC 14], though, with
the principles we now have for stable releases of Wasmtime. I'll close
out Lightbeam-related issues once this is merged.

[RFC 14]: https://github.com/bytecodealliance/rfcs/pull/14

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Fix a few typos in the architecture doc (#3054)

Start a high-level architecture document for Wasmtime (#3019)

* Start a high-level architecture document for Wasmtime

This commit cleands up some existing documentation by removing a number
of "

Start a high-level architecture document for Wasmtime (#3019)

* Start a high-level architecture document for Wasmtime

This commit cleands up some existing documentation by removing a number
of "noop README files" and starting a high-level overview of the
architecture of Wasmtime. I've placed this documentation under the
contributing section of the book since it seems most useful for possible
contributors.

I've surely left some things out in this pass, and am happy to add more!

* Review comments

* More rewording

* typos

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