Sync rustc_codegen_cranelift
The main highlight of this sync is removal of support for the old x86 Cranelift backend. This made it possible to use native atomic instructions rather than hackishly using a global mutex. 128bit integer support has also seen a few bugfixes and performance improvements. And finally I have formatted everything using the same rustfmt config as the rest of this repo.
r? ````@ghost````
````@rustbot```` label +A-codegen +A-cranelift +T-compiler
rustdoc: Add an unstable option to print all unversioned files
This allows sharing those files between different doc invocations
without having to know their names ahead of time.
Helps with https://github.com/rust-lang/docs.rs/issues/1302.
r? ````@GuillaumeGomez```` cc ````@pietroalbini```` ````@Nemo157````
improve offset_from docs
`@thomcc` pointed out that the current docs leave it kind of unclear how one can satisfy the "no wrapping around `isize` or the address space" requirement of `offset_from`, so make the docs clearer about that.
FWIW, I don't think I entirely agree with that second paragraph about large objects (that I left mostly unchanged here). LLVM, to my knowledge, fundamentally assumes that all allocations fit into an `isize::MAX`. So in that sense creating a larger allocation is simply UB. I would expect a guarantee that Rust heap allocation methods will never return allocations larger than `isize::MAX` (or rather, Rust heap allocation methods should require that the `Layout` is no larger than `isize::MAX`). However, I cannot find any such requirement documented currently. Large allocations are not mentioned at all in the allocator docs, which is quite surprising -- even if we say that such allocations are not insta-UB (which I think is incompatible with LLVM), they are still extremely footgunny since `ptr::offset`/`ptr::add` do not support offsetting by more than `isize::MAX` bytes.
Furthermore, the allocator docs don't even say anything about allocations wrapping around the address space. But that is certainly something allocators must ensure never happens; we cannot expect clients to defend against this.
Cc `@rust-lang/wg-allocators`
Cleanup rustdoc warnings
## Clean up error reporting for deprecated passes
Using `error!` here goes all the way back to the original commit, https://github.com/rust-lang/rust/pull/8540. I don't see any reason to use logging; rustdoc should use diagnostics wherever possible. See https://github.com/rust-lang/rust/pull/81932#issuecomment-785291244 for further context.
- Use spans for deprecated attributes
- Use a proper diagnostic for unknown passes, instead of error logging
- Add tests for unknown passes
- Improve some wording in diagnostics
## Report that `doc(plugins)` doesn't work using diagnostics instead of `eprintln!`
This also adds a test for the output.
This was added in https://github.com/rust-lang/rust/pull/52194. I don't see any particular reason not to use diagnostics here, I think it was just missed in https://github.com/rust-lang/rust/pull/50541.
Improve transmute docs with further clarifications
Closes#82493.
Please let me know if any of the new wording sounds off, English is not my mother tongue.
Remove RefCell around `module_trait_cache`
This builds on https://github.com/rust-lang/rust/pull/82018 and should not be merged before.
## Don't require a `DocContext` for `report_diagnostic`
This is needed for the next commit, which needs mutable access to the `cx` from
within the `decorate` closure.
- Change `as_local_hir_id` to an associated function, since it only
needs a `TyCtxt`
- Change `source_span_for_markdown_range` to only take a `TyCtxt`
## Remove RefCell around module_trait_cache
This is mostly just changing lots of functions from `&DocContext` to `&mut DocContext`.
Prevent specialized ZipImpl from calling `__iterator_get_unchecked` twice with the same index
Fixes#82291
It's open for review, but conflicts with #82289, wait before merging. The conflict involves only the new test, so it should be rather trivial to fix.
Make some Option, Result methods unstably const
The following methods are now unstably const:
- Option::transpose
- Option::flatten
- Result::flatten
While some methods for could likely be made `const` in the future, nearly all of them require something to be dropped at compile-time, which isn't currently supported. The functions listed above should have a trivial path to stabilization.
Change built-in kernel targets to be os = none throughout
Whether for Rust's own `target_os`, LLVM's triples, or GNU config's, the
OS-related have fields have been for code running *on* that OS, not code
hat is *part* of the OS.
The difference is huge, as syscall interfaces are nothing like
freestanding interfaces. Kernels are (hypervisors and other more exotic
situations aside) freestanding programs that use the interfaces provided
by the hardware. It's *those* interfaces, the ones external to the
program being built and its software dependencies, that are the content
of the target.
For the Linux Kernel in particular, `target_env: "gnu"` is removed for
the same reason: that `-gnu` refers to glibc or GNU/linux, neither of
which applies to the kernel itself.
Relates to #74247
Move check only relevant in error case out of critical path
Move the check for potentially forgotten `return` in a tail expression
of arbitrary expressions into the coercion error branch to avoid
computing unncessary coercion checks on successful code.
Follow up to #81458.
Rust contains various size checks conditional on target_arch = "x86_64",
but these checks were never intended to apply to
x86_64-unknown-linux-gnux32. Add target_pointer_width = "64" to the
conditions.
I don't think the boxing helped performance, in fact I think it
potentially made it worse. The data was still being copied, but now it
was through a pointer. Thinking about it more, I think boxing might only
help when you're passing a big object around by value all the time,
rather than the slowdown being that you're cloning it.
pierwill