Remove `avx512dq` and `avx512vl` implication for `avx512fp16`
According to Intel, `avx512fp16` requires only `avx512bw`, but LLVM also enables `avx512vl` and `avx512dq` when `avx512fp16` is active. This is relic code, and will be fixed in LLVM soon. We should remove this from Rust too asap, especially before the stabilization of AVX512
Related:
- llvm/llvm-project#136209
- #138940
- rust-lang/stdarch#1781
- #111137
``@rustbot`` label O-x86_64 O-x86_32 A-SIMD A-target-feature T-compiler -T-libs
r? ``@Amanieu``
**Update: the LLVM fix has been merged**
cc ``@rust-lang/wg-llvm`` will it be possible to update the rustc llvm version to something after llvm/llvm-project#137450
Avoid redundant WTF-8 checks in `PathBuf`
Eliminate checks for WTF-8 boundaries in `PathBuf::set_extension` and `add_extension`, where joining WTF-8 surrogate halves is impossible. Don't convert the `str` to `OsStr`, because `OsString::push` specializes to skip the joining when given strings.
To assist in this, mark the internal methods `OsString::truncate` and `extend_from_slice` as `unsafe` to communicate their safety invariants better than with module privacy.
Similar to #137777.
cc `@joboet` `@ChrisDenton`
Delegate to inner `vec::IntoIter` from `env::ArgsOs`
Delegate from `std::env::ArgsOs` to the methods of the inner platform-specific iterators, when it would be more efficient than just using the default methods of its own impl. Most platforms use `vec::IntoIter` as the inner type, so prioritize delegating to the methods it provides.
`std::env::Args` is implemented atop `std::env::ArgsOs` and performs UTF-8 validation with a panic for invalid data. This is a visible effect which users certainly rely on, so we can't skip any arguments. Any further iterator methods would skip some elements, so no change is needed for that type.
Add `#[inline]` for any methods which simply wrap the inner iterator.
Clarify `async` block behaviour
Adds some documentation for control flow behaviour pertaining to `return` and `?` within `async` blocks. Fixes (or at least improves) #101444.
r? rust-lang/docs
std: use the address of `errno` to identify threads in `unique_thread_exit`
Getting the address of `errno` should be just as cheap as `pthread_self()` and avoids having to use the expensive `Mutex` logic because it always results in a pointer.
rustc_target: RISC-V `Zfinx` is incompatible with `{ILP32,LP64}[FD]` ABIs
Because RISC-V Calling Conventions note that:
> This means code targeting the `Zfinx` extension always uses the ILP32, ILP32E or LP64 integer calling-convention only ABIs as there is no dedicated hardware floating-point register file.
`{ILP32,LP64}[FD]` ABIs with hardware floating-point calling conventions are incompatible with the `Zfinx` extension.
This commit adds `"zfinx"` to the incompatible feature list to those ABIs and tests whether trying to add `"zdinx"` (that is analogous to `"zfinx"` but in double-precision) on a LP64D ABI configuration results in an error (it also tests extension implication; `Zdinx` requires `Zfinx` extension).
Links: RISC-V psABI specification version 1.0
<https://github.com/riscv-non-isa/riscv-elf-psabi-doc/blob/v1.0/riscv-cc.adoc#named-abis>
<https://github.com/riscv-non-isa/riscv-elf-psabi-doc/releases/tag/v1.0>
handle paren in macro expand for let-init-else expr
Fixes#131655
This PR modifies the codegen logic of the macro expansion within `let-init-else` expression:
- Before: The expression `let xxx = (mac! {}) else {}` expands to `let xxx = (expanded_ast) else {}`.
- After: The same expression expands to `let xxx = expanded_ast else {}`.
An alternative solution to this issue could involve handling the source code directly when encountering unused parentheses in `let-init-else` expressions. However, this approach might be more cumbersome due to the absence of the necessary data structure.
r? `@petrochenkov`
Rollup of 12 pull requests
Successful merges:
- #138703 (chore: remove redundant words in comment)
- #139186 (Refactor `diy_float`)
- #139780 (docs: Add example to `Iterator::take` with `by_ref`)
- #139802 (Fix some grammar errors and hyperlinks in doc for `trait Allocator`)
- #140034 (simd_select_bitmask: the 'padding' bits in the mask are just ignored)
- #140062 (std: mention `remove_dir_all` can emit `DirectoryNotEmpty` when concurrently written into)
- #140420 (rustdoc: Fix doctest heuristic for main fn wrapping)
- #140460 (Fix handling of LoongArch target features not supported by LLVM 19)
- #140538 (rustc-dev-guide subtree update)
- #140544 (Clean up "const" situation in format_args!(). )
- #140552 (allow `#[rustc_std_internal_symbol]` in combination with `#[naked]`)
- #140556 (Improve error output in case `nodejs` or `npm` is not installed for rustdoc-gui test suite)
r? `@ghost`
`@rustbot` modify labels: rollup
By taking the existing `expanded-exhaustive.rs` test and running it with
both `Zunpretty=expanded` *and* `Zunpretty=hir`.
Also rename some files, and split the asm parts out so they only run on
x86-64.
Delegate from `std::env::ArgsOs` to the methods of the inner
platform-specific iterators, when it would be more efficient than just
using the default methods of its own impl. Most platforms use
`vec::IntoIter` as the inner type, so prioritize delegating to the
methods it provides.
`std::env::Args` is implemented atop `std::env::ArgsOs` and performs
UTF-8 validation with a panic for invalid data. This is a visible effect
which users certainly rely on, so we can't skip any arguments. Any
further iterator methods would skip some elements, so no change is
needed for that type.
Add `#[inline]` for any methods which simply wrap the inner iterator.
allow `#[rustc_std_internal_symbol]` in combination with `#[naked]`
The need for this came up in https://github.com/rust-lang/compiler-builtins/pull/897, but in general this seems useful and valid to allow.
Based on a quick scan, I don't think changes to the generated assembly are needed.
cc ``@bjorn3``
Clean up "const" situation in format_args!().
This cleans up the "const" situation in the format_args!() expansion/lowering.
Rather than marking the Argument::new_display etc. functions as non-const, this marks the Arguments::new_v1 functions as non-const.
Example expansion/lowering of format_args!() in const:
```rust
// Error: cannot call non-const formatting macro in constant functions
const {
fmt::Arguments::new_v1( // Now the error is produced here.
&["Hello, ", "!\n"],
&[
fmt::Argument::new_display(&world) // The error used to be produced here.
],
)
}
```
rustdoc: Fix doctest heuristic for main fn wrapping
Fixes#140412 which regressed in #140220 that I reviewed. As mentioned in https://github.com/rust-lang/rust/pull/140220#issuecomment-2837061779, at the time I didn't have the time to re-review its latest changes and should've therefore invalided my previous "r=me" and blocked the PR on another review given the fragile nature of the doctest impl. This didn't happen which is my fault.
Contains some other small changes. Diff best reviewed modulo whitespace.
r? ``@GuillaumeGomez``
std: mention `remove_dir_all` can emit `DirectoryNotEmpty` when concurrently written into
Closes#139958
The current documentation for `std::fs::remove_dir_all` function does not explicitly mention the error types that may be returned in concurrent scenarios. Specifically, when one thread attempts to remove a directory tree while another thread simultaneously writes files to that directory, the function may return an `io::ErrorKind::DirectoryNotEmpty` error, but this behavior is not clearly mentioned in the current documentation.
r? libs
simd_select_bitmask: the 'padding' bits in the mask are just ignored
Fixes https://github.com/rust-lang/rust/issues/137942: we documented simd_select_bitmask to require the 'padding' bits in the mask (the mask can sometimes be longer than the vector; I am referring to these extra bits as 'padding' here) to be zero, mostly because nobody felt like doing the research for what should be done when they are non-zero. However, codegen is already perfectly happy just ignoring them, so in practice they can have any value. Some of the intrinsic wrappers in stdarch have trouble ensuring that they are zero. So let's just adjust the docs and Miri to permit non-zero 'padding' bits.
Cc ````@Amanieu```` ````@workingjubilee````
Fix some grammar errors and hyperlinks in doc for `trait Allocator`
I was reading the allocator docs and noticed some weird sentences and missing hyperlink, so I fixed them and made this small PR.
* "while until either" could also be changed to "for a while until either", but I just deleted "while".
* fixed sentence with incorrect "at" and "has/have".
* linked [*currently allocated*] similar to other methods. All other hyperlinks are fine.
docs: Add example to `Iterator::take` with `by_ref`
If you want to logically split an iterator after `n` items, you might first discover `take`. Before this change, you'd find that `take` consumes the iterator, and you'd probably be stuck. The answer involves `by_ref`, but that's hard to discover, especially since `by_ref` is a bit abstract and `Iterator` has many methods.
After this change, you'd see the example showing `take` along with `by_ref`, which allows you to continue using the rest of the iterator. `by_ref` had a good example involving `take` already, so this change just duplicates that existing example under `take`.
Refactor `diy_float`
The refactor replaces bespoke algorithms with functions already inside the standard library, improving both codegen and readability.
Decouple SCC annotations from SCCs
This rewires SCC annotations to have them be a separate, visitor-type data structure. It was broken out of #130227, which needed them to be able to remove unused annotations after computation without recomputing the SCCs themselves.
As a drive-by it also removes some redundant code from the hot loop in SCC construction for a performance improvement.
r? lcnr
shared-generics: Do not share instantiations that contain local-only types
In Zed shared-generics loading takes up a significant chunk of time in incremental build, as rustc deserializes rmeta of all dependencies of a crate. I've recently realized that shared-generics includes all instantiations of some_generic_function in the following snippet:
```rs
pub fn some_generic_function(_: impl Fn()) {}
pub fn non_generic_function() {
some_generic_function(|| {});
some_generic_function(|| {});
some_generic_function(|| {});
some_generic_function(|| {});
some_generic_function(|| {});
some_generic_function(|| {});
some_generic_function(|| {});
}
```
even though none of these instantiations can actually be created from outside of `non_generic_function`. This is a dummy example, but we do rely on invoking callbacks with FnOnce a lot in our codebase.
This PR makes shared-generics account for visibilities of generic arguments; an item is only considered for exporting if it is reachable from the outside or if all of it's arguments are visible outside of the local crate.
This PR reduces incremental build time for Zed (touch editor.rs scenario) from 12.4s to 10.4s. I'd love to see a perf run if possible; per my checks this PR does not incur new instantiations in downstream crates, so if there'd be perf regressions, I'd expect them to come from newly-introduced visibility checks.
Eliminate checks for WTF-8 boundaries in `PathBuf::set_extension` and
`add_extension`, where joining WTF-8 surrogate halves is impossible.
Don't convert the `str` to `OsStr`, because `OsString::push` specializes
to skip the joining when given strings.
Because RISC-V Calling Conventions note that:
> This means code targeting the Zfinx extension always uses the ILP32,
> ILP32E or LP64 integer calling-convention only ABIs as there is no
> dedicated hardware floating-point register file.
{ILP32,LP64}[FD] ABIs with hardware floating-point calling conventions
are incompatible with the "Zfinx" extension.
This commit adds "zfinx" to the incompatible feature list to those ABIs
and tests whether trying to add "zdinx" (that is analogous to "zfinx" but
in double-precision) on a LP64D ABI configuration results in an error
(it also tests extension implication; "Zdinx" requires "Zfinx" extension).
Link: RISC-V psABI specification version 1.0
<https://github.com/riscv-non-isa/riscv-elf-psabi-doc/releases/tag/v1.0>
