Commit Graph

15840 Commits

Author SHA1 Message Date
Matthias Krüger e88067927a
Rollup merge of #128824 - GuillaumeGomez:update-compiler-builtins, r=Amanieu
Update compiler-builtins version to 0.1.118

r? `@Amanieu`
2024-08-09 05:52:16 +02:00
Matthias Krüger 5f0461707a
Rollup merge of #128818 - RalfJung:std-miri-floats, r=tgross35
std float tests: special-case Miri in feature detection

Quick work-around to fix miri-test-libstd failures.

r? ``@tgross35``
2024-08-09 00:03:37 +02:00
Matthias Krüger 95b40727bd
Rollup merge of #128640 - RalfJung:rwlock-macos-miri, r=joboet
rwlock: disable 'frob' test in Miri on macOS

Due to https://github.com/rust-lang/rust/issues/121950, Miri will sometimes complain about this test on macOS. Better disable the test, as otherwise it can fail for unrelated PRs.

r? ``@joboet``
2024-08-09 00:03:35 +02:00
Matthias Krüger 127fbc8481
Rollup merge of #128749 - tgross35:float-inline, r=scottmcm
Mark `{f32,f64}::{next_up,next_down,midpoint}` inline

Most float functions are marked `#[inline]` so any float symbols used by these functions only need to be provided if the function itself is used. RFL recently noticed that `next_up`, `next_down`, and `midpoint` for `f32` and `f64` are not inline, which causes linker errors when building with certain configurations <https://lore.kernel.org/all/20240806150619.192882-1-ojeda@kernel.org/>.

Add the missing attributes so the symbols should no longer be required.
2024-08-08 18:57:02 +02:00
Matthias Krüger 3a9dd829d0
Rollup merge of #128306 - WiktorPrzetacznik:WiktorPrzetacznik-nonnull-alignoffset-update, r=Amanieu
Update NonNull::align_offset quarantees

This PR proposes to update [`NonNull::align_offset`](https://doc.rust-lang.org/stable/std/ptr/struct.NonNull.html#method.align_offset) guarantees, which should to be matched with [`ptr::align_offset`](https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.align_offset-1)
(as `NonNull::align_offset` delegates to `ptr::align_offset`).

[PR #121201](https://github.com/rust-lang/rust/pull/121201) updated only `ptr::align_offset` docs.
2024-08-08 18:57:00 +02:00
Guillaume Gomez 6d69b2e408 Update compiler-builtins version to 0.1.118 2024-08-08 14:47:49 +02:00
Ralf Jung 5d968705b1 std float tests: special-case Miri in feature detection
also fix some cfg logic
2024-08-08 12:17:50 +02:00
Ralf Jung a120fb7031 rwlock: disable 'frob' test in Miri on macOS 2024-08-08 11:15:18 +02:00
Trevor Gross 36b9aee947
Rollup merge of #128800 - clarfonthey:core-pattern-type, r=compiler-errors
Add tracking issue to core-pattern-type

While the actual `pattern_types` feature flag has an issue assigned, the exported macro and its module do not.

cc #123646
2024-08-07 20:49:05 -05:00
Trevor Gross 1d820dc9a6
Rollup merge of #128691 - tgross35:update-builtins, r=Amanieu
Update `compiler-builtins` to 0.1.117

This includes [1] which means we can remove the (nonworking) configuration of `no-f16-f128`.

Fixes https://github.com/rust-lang/rust/issues/128401.

[1]: https://github.com/rust-lang/compiler-builtins/pull/652

try-job: dist-various-1
2024-08-07 20:49:03 -05:00
ltdk 0257f42089 Add tracking issue to core-pattern-type 2024-08-07 20:43:05 -04:00
Matthias Krüger 2ee9678338
Rollup merge of #128261 - clarfonthey:iter-default, r=dtolnay
impl `Default` for collection iterators that don't already have it

There is a pretty strong precedent for implementing `Default` for collection iterators, and this does so for some where this implementation was missed.

I don't think this needs a separate ACP (since this precedent already exists, and these feel like they were just missed), however, it *will* need an FCP since these implementations are instantly stable.
2024-08-07 20:28:16 +02:00
Trevor Gross 6b3feb49c6 Mark `{f32,f64}::{next_up,next_down,midpoint}` inline
Most float functions are marked `#[inline]` so any float symbols used by
these functions only need to be provided if the function itself is used.
RFL recently noticed that `next_up`, `next_down`, and `midpoint` for
`f32` and `f64` are not inline, which causes linker errors when building
with certain configurations [1].

Add the missing attributes so the symbols should no longer be required.

Cc: Gary Guo <gary@garyguo.net>
Reported-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/all/20240806150619.192882-1-ojeda@kernel.org/ [1]
2024-08-07 03:24:55 -05:00
Trevor Gross 701bc03c52
Rollup merge of #128766 - Monadic-Cat:patch-1, r=tgross35
Trivial grammar fix in const keyword docs

This PR makes a trivial fix to the wording of a sentence in the `const` keyword docs.

> `const` items looks remarkably similar to `static` items, [...]

Either this should be written as
> A `const` items looks remarkably similar to a `static` item, [...]

or "looks" should be changed to "look".

I have selected the smaller diff.
2024-08-06 22:17:35 -05:00
Trevor Gross b3bfd66627
Rollup merge of #128417 - tgross35:f16-f128-math, r=dtolnay
Add `f16` and `f128` math functions

This adds intrinsics and math functions for `f16` and `f128` floating point types. Support is quite limited and some things are broken so tests don't run on many platforms, but this provides a starting point.
2024-08-06 22:17:32 -05:00
Monadic Cat f34ff1e05a
Trivial grammar fix in const keyword docs
> `const` items looks remarkably similar to `static` items, [...]

Either this should be written as
> A `const` items looks remarkably similar to a `static` item,

or "looks" should be changed to "look".

I have selected the smaller diff.
2024-08-06 21:59:04 -05:00
Trevor Gross 51e68c3006 Update `compiler-builtins` to 0.1.117
This includes [1] which means we can remove the (nonworking)
configuration of `no-f16-f128`.

Fixes https://github.com/rust-lang/rust/issues/128401.

[1]: https://github.com/rust-lang/compiler-builtins/pull/652
2024-08-06 21:48:32 -05:00
Matthias Krüger 6ed9a33001
Rollup merge of #128751 - devnexen:vxworks_set_thread_name, r=tgross35
std:🧵 set_name implementation proposal for vxWorks.
2024-08-07 00:34:15 +02:00
Matthias Krüger f00a55188f
Rollup merge of #128539 - biabbas:deny_unsafe, r=workingjubilee
Forbid unused unsafe in vxworks-specific std modules

Tracking issue #127747
Adding deny(unsafe_op_in_unsafe_fn) in VxWorks specific files did not cause any error.
Most of VxWorks falls back on Unix libraries. So we'll have to wait for Unix changes.

r? ```@workingjubilee```
2024-08-07 00:34:12 +02:00
Matthias Krüger 7e1360b1e1
Rollup merge of #128406 - lolbinarycat:bufreader_peek, r=Mark-Simulacrum
implement BufReader::peek

Part of https://github.com/rust-lang/rust/issues/128405
2024-08-07 00:34:12 +02:00
Matthias Krüger 16b251be10
Rollup merge of #125048 - dingxiangfei2009:stable-deref, r=amanieu
PinCoerceUnsized trait into core

cc ``@Darksonn`` ``@wedsonaf`` ``@ojeda``

This is a PR to introduce a `PinCoerceUnsized` trait in order to make trait impls generated by the proc-macro `#[derive(SmartPointer)]`, proposed by [RFC](e17e19ac7a/text/3621-derive-smart-pointer.md (pincoerceunsized-1)), sound. There you may find explanation, justification and discussion about the alternatives.

Note that we do not seek stabilization of this `PinCoerceUnsized` trait in the near future. The stabilisation of this trait does not block the eventual stabilization process of the `#[derive(SmartPointer)]` macro. Ideally, use of `DerefPure` is more preferrable except this will actually constitute a breaking change. `PinCoerceUnsized` emerges as a solution to the said soundness hole while avoiding the breaking change. More details on the `DerefPure` option have been described in this [section](e17e19ac7a/text/3621-derive-smart-pointer.md (derefpure)) of the RFC linked above.

Earlier discussion can be found in this [Zulip stream](https://rust-lang.zulipchat.com/#narrow/stream/136281-t-opsem/topic/Pin.20and.20soundness.20of.20unsizing.20coercions) and [rust-for-linux thread](https://rust-lang.zulipchat.com/#narrow/stream/425075-rust-for-linux/topic/.23.5Bderive.28SmartPointer.29.5D.20and.20pin.20unsoundness.20rfc.233621).

try-job: dist-various-2
2024-08-07 00:34:11 +02:00
David Carlier b9e8e99198
std:🧵 set_name implementation proposal for vxWorks. 2024-08-06 21:10:12 +01:00
binarycat 4af77dfea5 implement BufReader::peek 2024-08-05 15:44:54 -04:00
Ralf Jung 212417b87f custom MIR: add support for tail calls 2024-08-05 18:23:14 +02:00
bors 4d48a6be74 Auto merge of #128673 - matthiaskrgr:rollup-gtvpkm7, r=matthiaskrgr
Rollup of 8 pull requests

Successful merges:

 - #128026 (std:🧵 available_parallelism implementation for vxWorks proposal.)
 - #128471 (rustdoc: Fix handling of `Self` type in search index and refactor its representation)
 - #128607 (Use `object` in `run-make/symbols-visibility`)
 - #128609 (Remove unnecessary constants from flt2dec dragon)
 - #128611 (run-make: Remove cygpath)
 - #128619 (Correct the const stabilization of `<[T]>::last_chunk`)
 - #128630 (docs(resolve): more explain about `target`)
 - #128660 (tests: more crashes)

r? `@ghost`
`@rustbot` modify labels: rollup
2024-08-05 06:55:50 +00:00
Matthias Krüger 74df517b90
Rollup merge of #128619 - glandium:last_chunk, r=scottmcm
Correct the const stabilization of `<[T]>::last_chunk`

`<[T]>::first_chunk` became const stable in 1.77, but `<[T]>::last_chunk` was left out. This was fixed in 3488679768, which reached stable in 1.80, making `<[T]>::last_chunk` const stable as of that version, but it is documented as being const stable as 1.77. While this is what should have happened, the documentation should reflect what actually did happen.
2024-08-05 08:22:24 +02:00
Matthias Krüger 1e951b70c7
Rollup merge of #128609 - swenson:smaller-faster-dragon, r=Amanieu
Remove unnecessary constants from flt2dec dragon

The "dragon" `flt2dec` algorithm uses multi-precision multiplication by (sometimes large) powers of 10. It has precomputed some values to help with these calculations.

BUT:

* There is no need to store powers of 10 and 2 * powers of 10: it is trivial to compute the second from the first.
* We can save a chunk of memory by storing powers of 5 instead of powers of 10 for the large powers (and just shifting as appropriate).
* This also slightly speeds up the routines (by ~1-3%) since the intermediate products are smaller and the shift is cheap.

In this PR, we remove the unnecessary constants and do the necessary adjustments.

Relevant benchmarks before (on my Threadripper 3970X, x86_64-unknown-linux-gnu):

```
num::flt2dec::bench_big_shortest                      137.92/iter   +/- 2.24
num::flt2dec::strategy:🐉:bench_big_exact_12   2135.28/iter  +/- 38.90
num::flt2dec::strategy:🐉:bench_big_exact_3     904.95/iter  +/- 10.58
num::flt2dec::strategy:🐉:bench_big_exact_inf 47230.33/iter +/- 320.84
num::flt2dec::strategy:🐉:bench_big_shortest   3915.05/iter  +/- 51.37
```

and after:

```
num::flt2dec::bench_big_shortest                      137.40/iter   +/- 2.03
num::flt2dec::strategy:🐉:bench_big_exact_12   2101.10/iter  +/- 25.63
num::flt2dec::strategy:🐉:bench_big_exact_3     873.86/iter   +/- 4.20
num::flt2dec::strategy:🐉:bench_big_exact_inf 47468.19/iter +/- 374.45
num::flt2dec::strategy:🐉:bench_big_shortest   3877.01/iter  +/- 45.74
```
2024-08-05 08:22:22 +02:00
Matthias Krüger 02c3837d8b
Rollup merge of #128026 - devnexen:available_parallelism_vxworks, r=Mark-Simulacrum
std:🧵 available_parallelism implementation for vxWorks proposal.
2024-08-05 08:22:21 +02:00
Matthias Krüger e4367cec5e
Rollup merge of #128309 - kmicklas:btreeset-cursor, r=Amanieu
Implement cursors for `BTreeSet`

Tracking issue: https://github.com/rust-lang/rust/issues/107540

This is a straightforward wrapping of the map API, except that map's `CursorMut` does not make sense, because there is no value to mutate. Hence, map's `CursorMutKey` is wrapped here as just `CursorMut`, since it's unambiguous for sets and we don't normally speak of "keys". On the other hand, I can see some potential for confusion with `CursorMut` meaning different things in each module. I'm happy to take suggestions to improve that.

r? ````@Amanieu````
2024-08-05 05:40:20 +02:00
Mike Hommey 70ab51f988 Correct the const stabilization of `<[T]>::last_chunk`
`<[T]>::first_chunk` became const stable in 1.77, but `<[T]>::last_chunk` was
left out. This was fixed in 3488679768, which reached stable in 1.80,
making `<[T]>::last_chunk` const stable as of that version, but it is
documented as being const stable as 1.77. While this is what should have
happened, the documentation should reflect what actually did happen.
2024-08-05 05:01:39 +09:00
bors 176e545209 Auto merge of #128534 - bjorn3:split_stdlib_workspace, r=Mark-Simulacrum
Move the standard library to a separate workspace

This ensures that the Cargo.lock packaged for it in the rust-src component is up-to-date, allowing rust-analyzer to run cargo metadata on the standard library even when the rust-src component is stored in a read-only location as is necessary for loading crates.io dependencies of the standard library.

This also simplifies tidy's license check for runtime dependencies as it can now look at all entries in library/Cargo.lock without having to filter for just the dependencies of runtime crates. In addition this allows removing an exception in check_runtime_license_exceptions that was necessary due to the compiler enabling a feature on the object crate which pulls in a dependency not allowed for the standard library.

While cargo workspaces normally enable dependencies of multiple targets to be reused, for the standard library we do not want this reusing to prevent conflicts between dependencies of the sysroot and of tools that are built using this sysroot. For this reason we already use an unstable cargo feature to ensure that any dependencies which would otherwise be shared get a different -Cmetadata argument as well as using separate build dirs.

This doesn't change the situation around vendoring. We already have several cargo workspaces that need to be vendored. Adding another one doesn't change much.

There are also no cargo profiles that are shared between the root workspace and the library workspace anyway, so it doesn't add any extra work when changing cargo profiles.
2024-08-04 18:40:03 +00:00
Matthias Krüger c8a33f7e34
Rollup merge of #128526 - tshepang:patch-1, r=Amanieu
time.rs: remove "Basic usage text"

Only one example is given (for each method)
2024-08-04 11:32:34 +02:00
bors b389b0ab72 Auto merge of #128466 - sayantn:stdarch-update, r=tgross35
Update the stdarch submodule

cc `@tgross35` `@Amanieu`
r? `@tgross35`

try-job: dist-various-2
2024-08-04 02:11:27 +00:00
sayantn 01bda01e33 Update stdarch 2024-08-04 03:40:21 +05:30
sayantn 2cde11f2d1 Chore: add `x86_amx_intrinsics` feature flag to `core/lib.rs` and remove `issue-120720-reduce-nan.rs` 2024-08-04 03:08:18 +05:30
Matthias Krüger 06133811a6
Rollup merge of #128551 - Konippi:refactor-backtrace-style-in-panic, r=tgross35
chore: refactor backtrace style in panic

# Refactor get_backtrace_style for better readability and potential performance improvements

This PR aims to improve the readability and maintainability of the `set_backtrace_style` and `get_backtrace_style` function.
2024-08-03 20:51:53 +02:00
Matthias Krüger 53a56190af
Rollup merge of #128530 - scottmcm:repeat-n-unchecked, r=joboet
Implement `UncheckedIterator` directly for `RepeatN`

This just pulls the code out of `next` into `next_unchecked`, rather than making the `Some` and `unwrap_unchecked`ing it.

And while I was touching it, I added a codegen test that `array::repeat` for something that's just `Clone`, not `Copy`, still ends up optimizing to the same thing as `[x; n]`: <https://rust.godbolt.org/z/YY3a5ajMW>.
2024-08-03 20:51:52 +02:00
Christopher Swenson 36a805939e Remove unnecessary constants from flt2dec dragon
The "dragon" `flt2dec` algorithm uses multi-precision multiplication by
(sometimes large) powers of 10. It has precomputed some values to help
with these calculations.

BUT:

* There is no need to store powers of 10 and 2 * powers of 10: it is
  trivial to compute the second from the first.
* We can save a chunk of memory by storing powers of 5 instead of powers
  of 10 for the large powers (and just shifting by 2 as appropriate).
* This also slightly speeds up the routines (by ~1-3%) since the
  intermediate products are smaller and the shift is cheap.

In this PR, we remove the unnecessary constants and do the necessary
adjustments.

Relevant benchmarks before (on my Threadripper 3970X, x86_64-unknown-linux-gnu):

```
num::flt2dec::bench_big_shortest                      137.92/iter   +/- 2.24
num::flt2dec::strategy:🐉:bench_big_exact_12   2135.28/iter  +/- 38.90
num::flt2dec::strategy:🐉:bench_big_exact_3     904.95/iter  +/- 10.58
num::flt2dec::strategy:🐉:bench_big_exact_inf 47230.33/iter +/- 320.84
num::flt2dec::strategy:🐉:bench_big_shortest   3915.05/iter  +/- 51.37
```

and after:

```
num::flt2dec::bench_big_shortest                      137.40/iter   +/- 2.03
num::flt2dec::strategy:🐉:bench_big_exact_12   2101.10/iter  +/- 25.63
num::flt2dec::strategy:🐉:bench_big_exact_3     873.86/iter   +/- 4.20
num::flt2dec::strategy:🐉:bench_big_exact_inf 47468.19/iter +/- 374.45
num::flt2dec::strategy:🐉:bench_big_shortest   3877.01/iter  +/- 45.74
```
2024-08-03 08:49:38 -07:00
bors 1f47624f9a Auto merge of #128404 - compiler-errors:revert-dead-code-changes, r=pnkfelix
Revert recent changes to dead code analysis

This is a revert to recent changes to dead code analysis, namely:
* efdf219 Rollup merge of #128104 - mu001999-contrib:fix/128053, r=petrochenkov
* a70dc297a8 Rollup merge of #127017 - mu001999-contrib:dead/enhance, r=pnkfelix
* 31fe9628cf Rollup merge of #127107 - mu001999-contrib:dead/enhance-2, r=pnkfelix
* 2724aeaaeb Rollup merge of #126618 - mu001999-contrib:dead/enhance, r=pnkfelix
* 977c5fd419 Rollup merge of #126315 - mu001999-contrib:fix/126289, r=petrochenkov
* 13314df21b Rollup merge of #125572 - mu001999-contrib:dead/enhance, r=pnkfelix

There is an additional change stacked on top, which suppresses false-negatives that were masked by this work. I believe the functions that are touched in that code are legitimately unused functions and the types are not reachable since this `AnonPipe` type is not publically reachable -- please correct me if I'm wrong cc `@NobodyXu` who added these in ##127153.

Some of these reverts (#126315 and #126618) are only included because it makes the revert apply cleanly, and I think these changes were only done to fix follow-ups from the other PRs?

I apologize for the size of the PR and the churn that it has on the codebase (and for reverting `@mu001999's` work here), but I'm putting this PR up because I am concerned that we're making ad-hoc changes to fix bugs that are fallout of these PRs, and I'd like to see these changes reimplemented in a way that's more separable from the existing dead code pass. I am happy to review any code to reapply these changes in a more separable way.

cc `@mu001999`
r? `@pnkfelix`

Fixes #128272
Fixes #126169
2024-08-03 13:04:30 +00:00
Michael Goulet cbd27db9a9 Suppress new false-negatives that were masked by dead code analysis changes 2024-08-03 07:57:31 -04:00
Michael Goulet 5f5b4ee128 Revert "Rollup merge of #127107 - mu001999-contrib:dead/enhance-2, r=pnkfelix"
This reverts commit 31fe9628cf, reversing
changes made to f20307851e.
2024-08-03 07:57:31 -04:00
Matthias Krüger 2f549aac39
Rollup merge of #128368 - nnethercote:rustfmt-tweaks, r=cuviper
Formatting tweaks

Some small post-#125443 formatting tweaks.

r? ``@cuviper``
2024-08-03 11:17:44 +02:00
Matthias Krüger 95d9f1c4ab
Rollup merge of #128303 - NobodyXu:specialise-for-pipe, r=cuviper
Enable `std::io::copy` specialisation for `std::pipe::{PipeReader, PipeWriter}`

Enable `std::io::copy` specialisation on unix for the newly added anonymous pipe API, tracking issue rust-lang/rust#127154
2024-08-03 11:17:43 +02:00
Matthias Krüger 1f700139f8
Rollup merge of #127586 - zachs18:more-must-use, r=cuviper
Add `#[must_use]` to some `into_raw*` functions.

cc #121287

r? ``@cuviper``

Adds `#[must_use = "losing the pointer will leak memory"]`[^1] to `Box::into_raw(_with_allocator)`, `Vec::into_raw_parts(_with_alloc)`, `String::into_raw_parts`[^2], and `rc::{Rc, Weak}::into_raw_with_allocator` (Rc's normal `into_raw` and all of `Arc`'s `into_raw*`s are already `must_use`).

Adds `#[must_use = "losing the raw <resource name may leak resources"]` to `IntoRawFd::into_raw_fd`, `IntoRawSocket::into_raw_socket`, and `IntoRawHandle::into_raw_handle`.

[^1]: "*will* leak memory" may be too-strong wording (since `Box`/`Vec`/`String`/`rc::Weak` might not have a backing allocation), but I left it as-is for simplicity and consistency.

[^2]: `String::into_raw_parts`'s `must_use` message is changed from the previous (possibly misleading) "`self` will be dropped if the result is not used".
2024-08-03 11:17:42 +02:00
Matthias Krüger 8aa18290a4
Rollup merge of #126704 - sayantn:sha, r=Amanieu
Added SHA512, SM3, SM4 target-features and `sha512_sm_x86` feature gate

This is an effort towards #126624. This adds support for these 3 target-features and introduces the feature flag `sha512_sm_x86`, which would gate these target-features and the yet-to-be-implemented detection and intrinsics in stdarch.
2024-08-03 11:17:41 +02:00
B I Mohammed Abbas c2c46e3e30 Forbid unsafe_op_in_unsafe_fn in vxworks specific os and sys files 2024-08-03 08:00:39 +05:30
Konippi a798e0f488 chore: refactor backtrace style in panic 2024-08-03 11:12:16 +09:00
bors 1df0458781 Auto merge of #128528 - workingjubilee:you-dont-need-to-see-this-cpuid-move-along, r=Amanieu
Finish removing `has_cpuid`

The one use of it was guaranteed to be always true.

try-job: test-various
2024-08-03 00:18:15 +00:00
bjorn3 1f3be75f56 Move the standard library to a separate workspace
This ensures that the Cargo.lock packaged for it in the rust-src
component is up-to-date, allowing rust-analyzer to run cargo metadata on
the standard library even when the rust-src component is stored in a
read-only location as is necessary for loading crates.io dependencies of
the standard library.

This also simplifies tidy's license check for runtime dependencies as it
can now look at all entries in library/Cargo.lock without having to
filter for just the dependencies of runtime crates. In addition this
allows removing an exception in check_runtime_license_exceptions that
was necessary due to the compiler enabling a feature on the object crate
which pulls in a dependency not allowed for the standard library.

While cargo workspaces normally enable dependencies of multiple targets
to be reused, for the standard library we do not want this reusing to
prevent conflicts between dependencies of the sysroot and of tools that
are built using this sysroot. For this reason we already use an unstable
cargo feature to ensure that any dependencies which would otherwise be
shared get a different -Cmetadata argument as well as using separate
build dirs.

This doesn't change the situation around vendoring. We already have
several cargo workspaces that need to be vendored. Adding another one
doesn't change much.

There are also no cargo profiles that are shared between the root
workspace and the library workspace anyway, so it doesn't add any extra
work when changing cargo profiles.
2024-08-02 10:48:12 +00:00
bors 19326022d2 Auto merge of #128254 - Amanieu:orig-binary-search, r=tgross35
Rewrite binary search implementation

This PR builds on top of #128250, which should be merged first.

This restores the original binary search implementation from #45333 which has the nice property of having a loop count that only depends on the size of the slice. This, along with explicit conditional moves from #128250, means that the entire binary search loop can be perfectly predicted by the branch predictor.

Additionally, LLVM is able to unroll the loop when the slice length is known at compile-time. This results in a very compact code sequence of 3-4 instructions per binary search step and zero branches.

Fixes #53823
Fixes #115271
2024-08-02 08:20:35 +00:00