Several fixes to debugging infrastructure: component vs. module PCs and gdbstub wasm module names. (#12901)

* Debugging: fix module-relative vs component-relative PCs and unique library names.

Two

Several fixes to debugging infrastructure: component vs. module PCs and gdbstub wasm module names. (#12901)

* Debugging: fix module-relative vs component-relative PCs and unique library names.

Two bugfixes for guest debugging with components:

1. Convert component-relative source locations to module-relative PCs
in the frame table. The guest-debug API presents a core-Wasm view
where components are deconstructed into individual modules, so all
PCs must be module-relative. This adds a `wasm_module_offset` field
to `ModuleTranslation` and `FuncEnvironment`, set during component
translation, and subtracts it in `debug_tags()`.

2. Give unique names to "library" entries in the gdbstub XML response.
LLDB's DynamicLoader deduplicates by name, so using "wasm" for all
modules caused only the first to be loaded.

* Debugging: add ModulePC and ComponentPC newtypes for Wasm PC offsets.

Introduce `ModulePC` (module-relative) and `ComponentPC`
(component-relative) newtype wrappers around u32 Wasm bytecode
offsets. These replace raw u32 values throughout the frame table,
breakpoint, and debug systems to prevent confusion between the two
offset spaces.

* Debugging: add regression test for component module-relative PCs.

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Debug: implement breakpoints and single-stepping. (#12133)

* Debug: implement breakpoints and single-stepping.

This is a PR that puts together a bunch of earlier pieces (patchable
calls in #12061 a

Debug: implement breakpoints and single-stepping. (#12133)

* Debug: implement breakpoints and single-stepping.

This is a PR that puts together a bunch of earlier pieces (patchable
calls in #12061 and #12101, private copies of code in #12051, and all
the prior debug event and instrumentation infrastructure) to implement
breakpoints in the guest debugger.

These are implemented in the way we have planned in #11964: each
sequence point (location prior to a Wasm opcode) is now a patchable call
instruction, patched out (replaced with NOPs) by default. When patched
in, the breakpoint callsite calls a trampoline with the `patchable` ABI
which then invokes the `breakpoint` hostcall. That hostcall emits the
debug event and nothing else.

A few of the interesting bits in this PR include:
- Implementations of "unpublish" (switch permissions back to read/write
from read/execute) for mmap'd code memory on all our platforms.
- Infrastructure in the frame-tables (debug info) metadata producer and
parser to record "breakpoint patches".
- A tweak to the NOP metadata packaged with the `MachBuffer` to allow
multiple NOP sizes. This lets us use one 5-byte NOP on x86-64, for
example (did you know x86-64 had these?!) rather than five 1-byte
NOPs.

This PR also implements single-stepping with a global-per-`Store` flag,
because at this point why not; it's a small additional bit of logic to
do *all* patches in all modules registered in the `Store` when that flag
is enabled.

A few realizations for future work:
- The need for an introspection API available to a debugger to see the
modules within a component is starting to become clear; either that,
or the "module and PC" location identifier for a breakpoint switches
to a "module or component" sum type. Right now, the tests for this
feature use only core modules. Extending to components should not
actually be hard at all, we just need to build the API for it.
- The interaction between inlining and `patchable_call` is interesting:
what happens if we inline a `patchable_call` at a `try_call` callsite?
Right now, we do *not* update the `patchable_call` to a `try_call`,
because there is no `patchable_try_call`; this is fine in the Wasmtime
embedding in practice because we never (today!) throw exceptions from
a breakpoint handler. This does suggest to me that maybe we should
make patchability a property of any callsite, and allow try-calls to
be patchable too (with the same restriction about no return values as
the only restriction); but happy to discuss that one further.

* Add missing debug.wat disas test.

* Review feedback.

* Fix comment on `CodeMemory::text_mut`.

* Review feedback.

* Review feedback: abort process on failure to re-apply executable permissions.

* Implement icache flush for aarch64.

This appears to be necessary as we otherwise see a failure in CI on
macOS/aarch64 that is consistent with patched-in breakpoint calls still
being incorrectly cached after we remove them and republish the code.

There is a longstanding issue in #3310 tracking proper icache coherence
handling on aarch64. We implemented this for Linux with the `membarrier`
syscall but never did so for macOS. Maybe this is the first point at
which it matters, because code was always loaded at new addresses (hence
did not have coherence issues because nothing would have been cached)
previously.

prtest:full

* Review feedback: use `next_multiple_of`.

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Wasmtime: implement debug instrumentation and basic host API to examine runtime state. (#11769)

* Wasmtime: implement debug instrumentation and basic host API to examine runtime state.

This PR impl

Wasmtime: implement debug instrumentation and basic host API to examine runtime state. (#11769)

* Wasmtime: implement debug instrumentation and basic host API to examine runtime state.

This PR implements ideas from the [recent RFC] to serve as the basis
for Wasm (guest) debugging: it adds a stackslot to each function
translated from Wasm, stores to replicate Wasm VM state in the
stackslot as the program runs, and metadata to describe the format of
that state and allow reading it out at runtime.

As an initial user of this state, this PR adds a basic "stack view"
API that, from host code that has been called from Wasm, can examine
Wasm frames currently on the stack and read out all of their locals
and stack slots.

Note in particular that this PR does not include breakpoints,
watchpoints, stepped execution, or any sort of user interface for any
of this; it is only a foundation.

This PR still has a few unsatisfying bits that I intend to address:

- The "stack view" performs some O(n) work when the view is initially
taken, computing some internal data per frame. This is forced by the
current design of `Backtrace`, which takes a closure and walks that
closure over stack frames eagerly (rather than work as an
iterator). It's got some impressive iterator-chain stuff going on
internally, so refactoring it to the latter approach might not
be *too* bad, but I haven't tackled it yet.

A O(1) stack view, that is, one that does work only for frames as
the host API is used to walk up the stack, is desirable because some
use-cases may want to quickly examine e.g. only the deepest
frame (say, running with a breakpoint condition that needs to read a
particular local's value after each step).

- It includes a new `Config::compiler_force_inlining()` option that is
used only for testing that we get the correct frames after
inlining. I couldn't get the existing flags to work on a Wasmtime
config level and suspect there may be an existing bug there; I will
try to split out a fix for it.

This PR renames the existing `debug` option to `native_debug`, to
distinguish it from the new approach.

[recent RFC]: https://github.com/bytecodealliance/rfcs/pull/44

* Update to new APIs on Cranelift side.

* Test update.

* Adjust objdump printing of InstPos on frame progpoints; and adjust progpoint collapsing.

* Convert to iterator form.

* Fix path in native-debug tests (debug -> native_debug rename).

* Enforce that `debug_instrumentation` can only be enabled when feature is enabled.

* Add missing assert.

* Use builtin knob for forcing intra-module inlining instead.

* Review feedback:

- Make StackView own the current frame rather than handing it out. This
prevents the current frame (`FrameView`) from walking away and hiding
somewhere it shouldn't, to be used unsoundly later.
- Assert no-GC during stack walk.

* Merge debug-instrumentation hooks on FuncEnvironment into before/after hooks.

* Review feedback: avoid downcasting funcs twice.

* Add debug feature to `wasmtime` crate's defaults.

* Review feedback: u32s for local and stack indices in debug host API.

* Use *const u8 as stack pointers and `with_exposed_provenance` in debug API.

* Remove some `srcloc` plumbing in Wasm translator.

* Rename native-debug back to debug, and make the new thing "guest debugging".

* rustfmt in debugging test.

* fix disas test after guest-debug CLI option rename.

* Review feedback: no separate debug-instrumentation hooks on FuncEnvironment.

* Review feedback: update doc comment on `Config::guest_debug`.

* Review feedback: rename `generate_debuginfo` to `debug_native` in tunables.

* Review feedback: miscellaneous comments.

* Review comment: fix wording in safety conditions.

* revert wasi-common submodule update

* Properly root values in debug frame slots.

Fixes #11841.

* Fix non-`debug`-feature build.

* Review feedback: naming.

* Ignore tests that compile modules in miri.

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Update Wasmtime to the 2024 Rust Edition (#10806)

* Update Wasmtime to the 2024 Rust Edition

Now that our MSRV supports the 2024 edition it's possible to make this
switch. This commit moves Wasmtim

Update Wasmtime to the 2024 Rust Edition (#10806)

* Update Wasmtime to the 2024 Rust Edition

Now that our MSRV supports the 2024 edition it's possible to make this
switch. This commit moves Wasmtime to the 2024 Edition to keep
up-to-date with Rust idioms and access many of the edition features
exclusive to the 2024 edition.

prtest:full

* Reformat with the 2024 edition

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Enable some Clippy conversion lints for `wasmtime-cranelift` (#9536)

Similar to how `wasmtime::runtime` has a few off-by-default lints turned
on for it do the same for the compilation phase of `wasm

Enable some Clippy conversion lints for `wasmtime-cranelift` (#9536)

Similar to how `wasmtime::runtime` has a few off-by-default lints turned
on for it do the same for the compilation phase of `wasmtime-cranelift`.
This is intended to help weed out lossy `as` casts and instead steer
users to `from` or `try_from` conversions.

show more ...

Fix rustdoc warnings on Nightly (#8258)

* Fix rustdoc warnings on Nightly

I noticed during a failed doc build of another PR we've got a number of
warnings being emitted, so resolve all those here.

Fix rustdoc warnings on Nightly (#8258)

* Fix rustdoc warnings on Nightly

I noticed during a failed doc build of another PR we've got a number of
warnings being emitted, so resolve all those here.

* Fix more warnings

* Fix rebase conflicts

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Exit through Cranelift-generated trampolines for builtins (#8152)

* Exit through Cranelift-generated trampolines for builtins

This commit changes how builtin functions in Wasmtime (think
`memory.gr

Exit through Cranelift-generated trampolines for builtins (#8152)

* Exit through Cranelift-generated trampolines for builtins

This commit changes how builtin functions in Wasmtime (think
`memory.grow`) are implemented. These functions are required to exit
through some manner of trampoline to handle runtime requirements for
backtracing right now. Currently this is done via inline assembly for
each architecture (or external assembly for s390x). This is a bit
unfortunate as it's a lot of hand-coding and making sure everything is
right, and it's not easy to update as it's multiple platforms to update.

The change in this commit is to instead use Cranelift-generated
trampolines for this purpose instead. The path for invoking a builtin
function now looks like:

* Wasm code calls a statically known symbol for each builtin.
* The statically known symbol will perform exit trampoline duties (e.g.
pc/fp/etc) and then load a function pointer to the host
implementation.
* The host implementation is invoked and then proceeds as usual.

The main new piece for this PR is that all wasm modules and functions
are compiled in parallel but an output of this compilation phase is what
builtin functions are required. All builtin functions are then unioned
together into one set and then anything required is generated just
afterwards. That means that only one builtin-trampoline per-module is
generated per-builtin.

This work is inspired by #8135 and my own personal desire to have as
much about our ABI details flowing through Cranelift as we can. This in
theory makes it more flexible to deal with future improvements to our
ABI.

prtest:full

* Fix some build issues

* Update winch test expectations

* Update Winch to use new builtin shims.

This commit refactors the Winch compiler to use the new trampolines for
all Wasmtime builtins created in the previous commits. This required a
fair bit of refactoring to handle plumbing through a new kind of
relocation and function call.

Winch's `FuncEnv` now contains a `PrimaryMap` from `UserExternalNameRef`
to `UserExternalName`. This is because there's now more than one kind of
name than just wasm function relocations, so the raw index space of
`UserExternalNameRef` is no longer applicable. This required threading
`FuncEnv` to more locations along with some refactorings to ensure that
lifetimes work out ok.

The `CompiledFunction` no longer stores a trait object of how to map
name refs to names and now directly has a `Primarymap`. This also means
that Winch's return value from its `TargetIsa` is a `CompiledFunction`
as opposed to the previous just-a-`MachBuffer` so it can also package up
all the relocation information. This ends up having `winch-codegen`
depend on `wasmtime-cranelift-shared` as a new dependency.

* Review feedback

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Remove the wasmtime-cranelift-shared crate (#8222)

The wasmtime-cranelift-shared crate is not as useful as it once was, as
it's no longer possible to build wasmtime with only winch; winch uses
the t

Remove the wasmtime-cranelift-shared crate (#8222)

The wasmtime-cranelift-shared crate is not as useful as it once was, as
it's no longer possible to build wasmtime with only winch; winch uses
the trampolines generated by cranelift now.

show more ...