…tors

* Choose test inputs more thoroughly and systematically.
* Check that `isqrt` and `checked_isqrt` have equivalent results for
  signed types, either equivalent numerically or equivalent as a panic
  and a `None`.
* Check that `isqrt` has numerically-equivalent results for unsigned
  types and their `NonZero` counterparts.
* Reuse `ilog10` benchmarks, plus benchmarks that use a uniform
  distribution.

* Use a lookup table for 8-bit integers and the Karatsuba square root
  algorithm for larger integers.
* Include optimization hints that give the compiler the exact numeric
  range of results.

Add various aarch64 features already supported by LLVM and Linux.

The features are marked as unstable using a newly added symbol, i.e.
aarch64_unstable_target_feature.

Additionally include some comment fixes to ensure consistency of
feature names with the Arm ARM and support for architecture version
target features up to v9.5a.

This commit adds compiler support for the following features:

- FEAT_CSSC
- FEAT_ECV
- FEAT_FAMINMAX
- FEAT_FLAGM2
- FEAT_FP8
- FEAT_FP8DOT2
- FEAT_FP8DOT4
- FEAT_FP8FMA
- FEAT_FPMR
- FEAT_HBC
- FEAT_LSE128
- FEAT_LSE2
- FEAT_LUT
- FEAT_MOPS
- FEAT_LRCPC3
- FEAT_SVE_B16B16
- FEAT_SVE2p1
- FEAT_WFxT

Add SME aarch64 features already supported by LLVM and Linux.

This commit adds compiler support for the following features:

- FEAT_SME
- FEAT_SME_F16F16
- FEAT_SME_F64F64
- FEAT_SME_F8F16
- FEAT_SME_F8F32
- FEAT_SME_FA64
- FEAT_SME_I16I64
- FEAT_SME_LUTv2
- FEAT_SME2
- FEAT_SME2p1
- FEAT_SSVE_FP8DOT2
- FEAT_SSVE_FP8DOT4
- FEAT_SSVE_FP8FMA

FEAT_FPMR has been removed from upstream LLVM as of LLVM 19.
Remove the feature from the target features list and temporarily hack
the LLVM codegen to always enable it until the minimum LLVM version is
bumped to 19.

Convert to_llvm_features to return Option<LLVMFeature> so that it can
return None if the requested feature is not available for the current
LLVM version.

Add match rules to filter out aarch64 features not available in LLVM 17.

Additionally, remove optional matching for +v8a given that the minimum LLVM version is now past 14.

A partial stabilization that only affects:
- AllocType<T>::new_uninit
- AllocType<T>::assume_init
- AllocType<[T]>::new_uninit_slice
- AllocType<[T]>::assume_init
where "AllocType" is Box, Rc, or Arc

…er error messages

```
error[E0282]: type annotations needed for `Box<_>`
  --> ~/.cargo/registry/src/index.crates.io-6f17d22bba15001f/time-0.3.34/src/format_description/parse/mod.rs:83:9
   |
83 |     let items = format_items
   |         ^^^^^
...
86 |     Ok(items.into())
   |              ---- type must be known at this point
   |
   = note: this is an inference error on crate `time` caused by a change in Rust 1.80.0; update `time` to version `>=0.3.35`
```

Partially address rust-lang#127343.

Signed-off-by: Amjad Alsharafi <26300843+Amjad50@users.noreply.github.com>

Improved `checked_isqrt` and `isqrt` methods

### Improved tests of `isqrt` and `checked_isqrt` implementations

* Inputs chosen more thoroughly and systematically.
* Checks that `isqrt` and `checked_isqrt` have equivalent results for signed types, either equivalent numerically or equivalent as a panic and a `None`.
* Checks that `isqrt` has numerically-equivalent results for unsigned types and their `NonZero` counterparts.

### Added benchmarks for `isqrt` implementations

### Greatly sped up `checked_isqrt` and `isqrt` methods

* Uses a lookup table for 8-bit integers and then the Karatsuba square root algorithm for larger integers.
* Includes optimization hints that give the compiler the exact numeric range of results.

### Feature tracking issue

`isqrt` is an unstable feature tracked at rust-lang#116226.

<details><summary>Benchmarked improvements</summary>

### Command used to benchmark

    ./x bench library/core -- int_sqrt

### Before

    benchmarks:
        num::int_sqrt::i128::isqrt           439591.65/iter  +/- 6652.70
        num::int_sqrt::i16::isqrt              5302.97/iter   +/- 160.93
        num::int_sqrt::i32::isqrt             62999.11/iter  +/- 2022.05
        num::int_sqrt::i64::isqrt            125248.81/iter  +/- 1674.43
        num::int_sqrt::i8::isqrt                123.56/iter     +/- 1.87
        num::int_sqrt::isize::isqrt          125356.56/iter  +/- 1017.03
        num::int_sqrt::non_zero_u128::isqrt  437443.75/iter  +/- 3535.43
        num::int_sqrt::non_zero_u16::isqrt     8604.58/iter    +/- 94.76
        num::int_sqrt::non_zero_u32::isqrt    62933.33/iter   +/- 517.30
        num::int_sqrt::non_zero_u64::isqrt   125076.38/iter +/- 11340.61
        num::int_sqrt::non_zero_u8::isqrt       221.51/iter     +/- 1.58
        num::int_sqrt::non_zero_usize::isqrt 136005.21/iter  +/- 2020.35
        num::int_sqrt::u128::isqrt           439014.55/iter  +/- 3920.45
        num::int_sqrt::u16::isqrt              8575.08/iter   +/- 148.06
        num::int_sqrt::u32::isqrt             63008.89/iter   +/- 803.67
        num::int_sqrt::u64::isqrt            125088.09/iter   +/- 879.29
        num::int_sqrt::u8::isqrt                230.18/iter     +/- 2.04
        num::int_sqrt::usize::isqrt          125237.51/iter  +/- 4747.83
### After

    benchmarks:
        num::int_sqrt::i128::isqrt           105184.89/iter +/- 1171.38
        num::int_sqrt::i16::isqrt              1910.26/iter   +/- 78.50
        num::int_sqrt::i32::isqrt             34260.34/iter  +/- 960.84
        num::int_sqrt::i64::isqrt             45939.19/iter +/- 2525.65
        num::int_sqrt::i8::isqrt                 22.87/iter    +/- 0.45
        num::int_sqrt::isize::isqrt           45884.17/iter  +/- 595.49
        num::int_sqrt::non_zero_u128::isqrt  106344.27/iter  +/- 780.99
        num::int_sqrt::non_zero_u16::isqrt     2790.19/iter   +/- 53.43
        num::int_sqrt::non_zero_u32::isqrt    33613.99/iter  +/- 362.96
        num::int_sqrt::non_zero_u64::isqrt    46235.42/iter  +/- 429.69
        num::int_sqrt::non_zero_u8::isqrt        31.78/iter    +/- 0.75
        num::int_sqrt::non_zero_usize::isqrt  46208.75/iter  +/- 375.27
        num::int_sqrt::u128::isqrt           106385.94/iter +/- 1649.95
        num::int_sqrt::u16::isqrt              2747.69/iter   +/- 28.72
        num::int_sqrt::u32::isqrt             33627.09/iter  +/- 475.68
        num::int_sqrt::u64::isqrt             46182.29/iter  +/- 311.16
        num::int_sqrt::u8::isqrt                 33.10/iter    +/- 0.30
        num::int_sqrt::usize::isqrt           46165.00/iter  +/- 388.41

</details>

rustc_target: Add various aarch64 features

Add various aarch64 features already supported by LLVM and Linux.
Additionally include some comment fixes to ensure consistency of feature names with the Arm ARM.
Compiler support for features added to stdarch by rust-lang/stdarch#1614.
Tracking issue for unstable aarch64 features is rust-lang#127764.

List of added features:

- FEAT_CSSC
- FEAT_ECV
- FEAT_FAMINMAX
- FEAT_FLAGM2
- FEAT_FP8
- FEAT_FP8DOT2
- FEAT_FP8DOT4
- FEAT_FP8FMA
- FEAT_HBC
- FEAT_LSE128
- FEAT_LSE2
- FEAT_LUT
- FEAT_MOPS
- FEAT_LRCPC3
- FEAT_SVE_B16B16
- FEAT_SVE2p1
- FEAT_WFxT
- FEAT_SME
- FEAT_SME_F16F16
- FEAT_SME_F64F64
- FEAT_SME_F8F16
- FEAT_SME_F8F32
- FEAT_SME_FA64
- FEAT_SME_I16I64
- FEAT_SME_LUTv2
- FEAT_SME2
- FEAT_SME2p1
- FEAT_SSVE_FP8DOT2
- FEAT_SSVE_FP8DOT4
- FEAT_SSVE_FP8FMA

FEAT_FPMR is added in the first commit and then removed in a separate one to highlight it being removed from upstream LLVM 19. The intention is for it to be detectable at runtime through stdarch but not have a corresponding Rust compile-time feature.

…celinval

Add an ability to convert between `Span` and `visit::Location`

AFAIK, there is no way to create a `Location` from a `Span` because its only field is private. This makes it impossible to use visitor methods like `visit_statement` or `visit_terminator`.

This PR adds an implementation for`From<Span>` for `Location` to fix this.

r? ``@celinval``

Emit specific message for time<=0.3.35

```
error[E0282]: type annotations needed for `Box<_>`
  --> /home/gh-estebank/.cargo/registry/src/index.crates.io-6f17d22bba15001f/time-0.3.34/src/format_description/parse/mod.rs:83:9
   |
83 |     let items = format_items
   |         ^^^^^
...
86 |     Ok(items.into())
   |              ---- type must be known at this point
   |
   = note: this is an inference error on `time` caused by a change in Rust 1.80.0; update `time` to version `>=0.3.36`
```

Partially mitigate the fallout from rust-lang#127343. Although the biggest benefit of this would have been if we had had this in 1.80 before it became stable, the long-tail of that change will be felt for a *long* time, so better late than never.

We can also emit an even more targeted error instead of this inference failure.

Clean up cfg-gating of ProcessPrng extern

This removes a bit of duplication and is consistent with how `api-ms-win-core-synch-l1-2-0` externs are imported.

…ion-of-stabilization, r=dtolnay,joboet

Partially stabilize `feature(new_uninit)`

Finished comment period: rust-lang#63291 (comment)

The following API has been stabilized from rust-lang#63291

```rust
impl<T> Box<T> { pub fn new_uninit() -> Box<MaybeUninit<T>> {…} }
impl<T> Rc<T> { pub fn new_uninit() -> Rc<MaybeUninit<T>> {…} }
impl<T> Arc<T> { pub fn new_uninit() -> Arc<MaybeUninit<T>> {…} }

impl<T> Box<[T]> { pub fn new_uninit_slice(len: usize) -> Box<[MaybeUninit<T>]> {…} }
impl<T> Rc<[T]> { pub fn new_uninit_slice(len: usize) -> Rc<[MaybeUninit<T>]> {…} }
impl<T> Arc<[T]> { pub fn new_uninit_slice(len: usize) -> Arc<[MaybeUninit<T>]> {…} }

impl<T> Box<MaybeUninit<T>> { pub unsafe fn assume_init(self) -> Box<T> {…} }
impl<T> Box<[MaybeUninit<T>]> { pub unsafe fn assume_init(self) -> Box<[T]> {…} }
impl<T> Rc<MaybeUninit<T>> { pub unsafe fn assume_init(self) -> Rc<T> {…} }
impl<T> Rc<[MaybeUninit<T>]> { pub unsafe fn assume_init(self) -> Rc<[T]> {…} }
impl<T> Arc<MaybeUninit<T>> { pub unsafe fn assume_init(self) -> Arc<T> {…} }
impl<T> Arc<[MaybeUninit<T>]> { pub unsafe fn assume_init(self) -> Arc<[T]> {…} }
```

The remaining API is split between new issues
- `new_zeroed_alloc`: rust-lang#129396
- `box_uninit_write`: rust-lang#129397

All relevant code is thus either stabilized or split out of that issue, so this closes rust-lang#63291 as, with the FCP concluded, that issue has served its purpose.

try-job: x86_64-rust-for-linux

…ax-pointee, r=compiler-errors

derive(SmartPointer): assume pointee from the single generic and better error messages

Fix rust-lang#129465

Actually RFC says that `#[pointee]` can be inferred when there is no ambiguity, or there is only one generic type parameter so to say.

cc ``@Darksonn``

r? ``@compiler-errors``

…adrieril

format code in tests/ui/threads-sendsync

was thinking of fixing formatting for 1 test in the directory, but found a bunch of them to also be in need

Update books

## rust-lang/book

4 commits in 04bc1396bb857f35b5dda1d773c9571e1f253304..e7d217be2a75ef1753f0988d6ccaba4d7e376259
2024-08-14 01:19:47 UTC to 2024-08-13 16:51:00 UTC

- Backport/forward port ch12 (rust-lang/book#4008)
- Found some more things to fix in ch7; I forgot to update the snapshot (rust-lang/book#4007)
- Remove redundant sentence. Send to nostarch (rust-lang/book#4006)
- Fix: typo (rust-lang/book#4003)

## rust-lang/edition-guide

5 commits in aeeb287d41a0332c210da122bea8e0e91844ab3e..eeba2cb9c37ab74118a4fb5e5233f7397e4a91f8
2024-08-19 23:28:06 UTC to 2024-08-15 15:12:33 UTC

- 2024: Add rustdoc combined doctests (rust-lang/edition-guide#320)
- Update for unsafe attributes stabilization (rust-lang/edition-guide#319)
- 2024: Add macro-fragment-specifiers. (rust-lang/edition-guide#312)
- Fix deprecated_safe_2024 link (rust-lang/edition-guide#317)
- Add 2024 unsafe functions (rust-lang/edition-guide#304)

## rust-embedded/book

1 commits in 019f3928d8b939ec71b63722dcc2e46330156441..ff5d61d56f11e1986bfa9652c6aff7731576c37d
2024-08-20 07:26:19 UTC to 2024-08-20 07:26:19 UTC

- Use aligned address to demonstrate HardFault (rust-embedded/book#374)

## rust-lang/nomicon

1 commits in 6ecf95c5f2bfa0e6314dfe282bf775fd1405f7e9..14649f15d232d509478206ee9ed5105641aa60d0
2024-08-14 14:49:09 UTC to 2024-08-14 14:49:09 UTC

- CI: Switch to merge queue (rust-lang/nomicon#459)

## rust-lang/reference

14 commits in 62cd0df95061ba0ac886333f5cd7f3012f149da1..0668397076da350c404dadcf07b6cbc433ad3743
2024-08-11 21:06:12 +0000 to 2024-08-27 21:47:20 +0000
- Update enum.md (rust-lang/reference#1354)
- Be consistent about how "Edition differences" is capitalized (rust-lang/reference#1586)
- Sync denied lints with upstream (rust-lang/reference#1589)
- const_eval: update for const-fn float stabilization (rust-lang/reference#1566)
- Add spec identifier syntax to destructors.md (rust-lang/reference#1571)
- Say that `pub(in path)` can't depend on `use` statements (rust-lang/reference#1559)
- bytes inside implicitly const-promoted expressions are immutable (rust-lang/reference#1554)
- Tweak `repr(transparent)` to mention requiring *at most* one non-1-ZST (rust-lang/reference#1568)
- operator expressions: add &raw (rust-lang/reference#1567)
- Rewrite the automatic std link translation, and switch to automatic links (rust-lang/reference#1578)
- Add some basic docs for unsafe attrs (rust-lang/reference#1539)
- don't capitalize Undefined Behavior (rust-lang/reference#1575)
- add the `const` operand to docs for inline assembly (rust-lang/reference#1556)
- Typo: 'a' to 'an' in type-coercions.md (rust-lang/reference#1572)

## rust-lang/rust-by-example

1 commits in 8f94061936e492159f4f6c09c0f917a7521893ff..859786c5bc99301bbc22fc631a5c2b341860da08
2024-08-26 10:30:48 UTC to 2024-08-26 10:30:48 UTC

- Update primitives.md with examples (rust-lang/rust-by-example#1878)

## rust-lang/rustc-dev-guide

7 commits in 43d83780db545a1ed6d45773312fc578987e3968..fa928a6d19e1666d8d811dfe3fd35cdad3b4e459
2024-08-26 14:46:50 UTC to 2024-08-12 21:07:49 UTC

- Fix x.py reference (rust-lang/rustc-dev-guide#2049)
- Update `stabilization_guide.md` (rust-lang/rustc-dev-guide#2034)
- Explain the internal `#[rustc_*]` TEST attributes used for debugging and inside tests (rust-lang/rustc-dev-guide#2046)
- missing char (rust-lang/rustc-dev-guide#2047)
- Replace direct http links to rustc-dev-guide.rust-lang.org (rust-lang/rustc-dev-guide#2044)
- Update index.html, 39. The MIR: fix typo (rust-lang/rustc-dev-guide#2043)
- Update LLVM docs (rust-lang/rustc-dev-guide#2039)

… r=dtolnay

Add fmt::Debug to sync::Weak<T, A>

Currently, `sync::Weak<T>` implements `Debug`, but `sync::Weak<T, A>` does not. This appears to be an oversight, as `rc::Weak<T, A>` implements `Debug`. (Note: `sync::Weak` is the weak for `Arc`, and `rc::Weak` is the weak for `Rc`.)

This PR adds the Debug trait for `sync::Weak<T, A>`. The issue was initially brought up here: rust-lang/wg-allocators#131

copysign with sign being a NaN can have non-portable results

Follow-up to rust-lang#129559.
Cc ``@tgross35`` ``@beetrees``

There's no portable variant we can recommend instead here, is there? Something with a semantics like "if `sign` is a NaN, then return `self` unaltered, otherwise return `self` with the sign changed to that of `sign`"?

…path, r=onur-ozkan

Fix path to run clippy on rustdoc

Took me a while to find out that the path clippy expected was `src/tools/rustdoc` and not `src/librustdoc`. I think it makes more sense this way as most commands rely on source paths.

r? ``@Kobzol``

…saethlin

Correct trusty targets to be tier 3

The Trusty targets were added in rust-lang#129490, but in that PR I accidentally marked them as tier 2. This PR corrects the target metadata to mark them as tier 3.

…r=tgross35

Update `compiler_builtins` to `0.1.123`

Includes rust-lang/compiler-builtins#680 and fixes rust-lang#128386.

Fixed by not including math symbols of `compiler_builtins` into any `unix` target or `wasi`, old behavior is restored

r? tgross35