compiler: remove unnecessary imports and qualified paths
Some of these imports were necessary before Edition 2021, others were already in the prelude.
I hope it's fine that this PR is so spread-out across files :/
Some method confirmation code nits
1. Make some pick methods take `&self` instead of `&mut` to avoid some cloning
2. Pass some values by reference to avoid some cloning
3. Rename a few variables here and there
Fix invalid codegen during debuginfo lowering
In order for LLVM to correctly generate debuginfo for msvc, we sometimes need to spill arguments to the stack and perform some direct & indirect offsets into the value. Previously, this code always performed those actions, even when not required as LLVM would clean it up during optimization.
However, when MIR inlining is enabled, this can cause problems as the operations occur prior to the spilled value being initialized. To solve this, we first calculate the necessary offsets using just the type which is side-effect free and does not alter the LLVM IR. Then, if we are in a situation which requires us to generate the LLVM IR (and this situation only occurs for arguments, not local variables) then we perform the same calculation again, this time generating the appropriate LLVM IR as we go.
r? `@tmiasko` but feel free to reassign if you want 🙂Fixes#105386
Avoid heap allocation when truncating thread names
Ensure that heap allocation does not occur in a thread until `std::thread` is ready. This fixes issues with custom allocators that call `std:🧵:current()`, since doing so prematurely initializes `THREAD_INFO` and causes the following `thread_info::set()` to fail.
Migrate parts of `rustc_expand` to session diagnostics
This migrates everything but the `mbe` and `proc_macro` modules. It also contains a few cleanups and drive-by/accidental diagnostic improvements which can be seen in the diff for the UI tests.
Fix failing codegen tests on s390x
Several codegen tests are currently failing due to making assumptions that are not valid for the s390x architecture:
- catch-unwind.rs: fails due to inlining differences. Already ignored on another platform for the same reason. Solution: Ignore on s390x.
- remap_path_prefix/main.rs: fails due to different alignment requirement for string constants. Solution: Do not test for the alignment requirement.
- repr-transparent-aggregates-1.rs: many ABI assumptions. Already ignored on many platforms for the same reason. Solution: Ignore on s390x.
- repr-transparent.rs: no vector ABI by default on s390x. Already ignored on another platform for a similar reason. Solution: Ignore on s390x.
- uninit-consts.rs: hard-coded little-endian constant. Solution: Match both little- and big-endian versions.
Fixes part of https://github.com/rust-lang/rust/issues/105383.
Rollup of 10 pull requests
Successful merges:
- #98391 (Reimplement std's thread parker on top of events on SGX)
- #104019 (Compute generator sizes with `-Zprint_type_sizes`)
- #104512 (Set `download-ci-llvm = "if-available"` by default when `channel = dev`)
- #104901 (Implement masking in FileType comparison on Unix)
- #105082 (Fix Async Generator ABI)
- #105109 (Add LLVM KCFI support to the Rust compiler)
- #105505 (Don't warn about unused parens when they are used by yeet expr)
- #105514 (Introduce `Span::is_visible`)
- #105516 (Update cargo)
- #105522 (Remove wrong note for short circuiting operators)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
This migrates everything but the `mbe` and `proc_macro` modules. It also
contains a few cleanups and drive-by/accidental diagnostic improvements
which can be seen in the diff for the UI tests.
Remove wrong note for short circuiting operators
They *are* representable by traits, even if the short-circuiting behaviour requires a different approach than the non-short-circuiting operators. For an example proposal, see the postponed [RFC 2722](https://github.com/rust-lang/rfcs/pull/2722). As it is not accurate, remove most of the note.
Add LLVM KCFI support to the Rust compiler
This PR adds LLVM Kernel Control Flow Integrity (KCFI) support to the Rust compiler. It initially provides forward-edge control flow protection for operating systems kernels for Rust-compiled code only by aggregating function pointers in groups identified by their return and parameter types. (See llvm/llvm-project@cff5bef.)
Forward-edge control flow protection for C or C++ and Rust -compiled code "mixed binaries" (i.e., for when C or C++ and Rust -compiled code share the same virtual address space) will be provided in later work as part of this project by identifying C char and integer type uses at the time types are encoded (see Type metadata in the design document in the tracking issue #89653).
LLVM KCFI can be enabled with -Zsanitizer=kcfi.
Thank you again, `@bjorn3,` `@eddyb,` `@nagisa,` and `@ojeda,` for all the help!
Fix Async Generator ABI
This change was missed when making async generators implement `Future` directly.
It did not cause any problems in codegen so far, as `GeneratorState<(), Output>`
happens to have the same ABI as `Poll<Output>`.
Set `download-ci-llvm = "if-available"` by default when `channel = dev`
See https://github.com/rust-lang/compiler-team/issues/566. The motivation for changing the default is to avoid downloading and building LLVM when someone runs `x build` before running `x setup`. The motivation for only doing it on `channel = "dev"` is to avoid breaking distros or users installing from source. It works because `dev` is also the default channel.
The diff looks larger than it is; most of it is moving the `llvm` branch below the `rust` so `config.channel` is set.
r? `@Mark-Simulacrum` cc `@oli-obk` `@bjorn3` `@cuviper`
Reimplement std's thread parker on top of events on SGX
Mutex and Condvar are being replaced by more efficient implementations, which need thread parking themselves (see #93740). Therefore, the generic `Parker` needs to be replaced on all platforms where the new lock implementation will be used.
SGX enclaves have a per-thread event state, which allows waiting for and setting specific bits. This is already used by the current mutex implementation. The thread parker can however be much more efficient, as it only needs to store the `TCS` address of one thread. This address is stored in a state variable, which can also be set to indicate the thread was already notified.
`park_timeout` does not guard against spurious wakeups like the current condition variable does. This is allowed by the API of `Parker`, and I think it is better to let users handle these wakeups themselves as the guarding is quite expensive and might not be necessary.
`@jethrogb` as you wrote the initial SGX support for `std`, I assume you are the target maintainer? Could you help me test this, please? Lacking a x86_64 chip, I can't run SGX.
They *are* representable by traits, even if the short-circuiting
behaviour requires a different approach than the non-short-circuiting
operators. For an example proposal, see the postponed RFC 2722.
As it is not accurate, reword the note.
Rollup of 9 pull requests
Successful merges:
- #102406 (Make `missing_copy_implementations` more cautious)
- #105265 (Add `rustc_on_unimplemented` to `Sum` and `Product` trait.)
- #105385 (Skip test on s390x as LLD does not support the platform)
- #105453 (Make `VecDeque::from_iter` O(1) from `vec(_deque)::IntoIter`)
- #105468 (Mangle "main" as "__main_void" on wasm32-wasi)
- #105480 (rustdoc: remove no-op mobile CSS `#sidebar-toggle { text-align }`)
- #105489 (Fix typo in apple_base.rs)
- #105504 (rustdoc: make stability badge CSS more consistent)
- #105506 (Tweak `rustc_must_implement_one_of` diagnostic output)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
rustdoc: remove no-op mobile CSS `#sidebar-toggle { text-align }`
Since 8b001b4da0 make the sidebar toggle a flex container, and already centers its content in desktop mode, this rule doesn't do anything.
Mangle "main" as "__main_void" on wasm32-wasi
On wasm, the age-old C trick of having a main function which can either have no arguments or argc+argv doesn't work, because wasm requires caller and callee signatures to match. WASI's current strategy is to have compilers mangle main's name to indicate which signature they're using. Rust uses the no-argument form, which should be mangled as `__main_void`.
This is needed on wasm32-wasi as of #105395.
Make `VecDeque::from_iter` O(1) from `vec(_deque)::IntoIter`
As suggested in https://github.com/rust-lang/rust/pull/105046#issuecomment-1330371695 by
r? ``@the8472``
`Vec` & `VecDeque`'s `IntoIter`s own the allocations, and even if advanced can be turned into `VecDeque`s in O(1).
This is just a specialization, not an API or doc commitment, so I don't think it needs an FCP.
