[rustc_ty_utils] Treat `drop_in_place`'s *mut argument like &mut when adding LLVM attributes
This resurrects PR #103614, which has sat idle for a while.
This could probably use a new perf run, since we're on a new LLVM version now.
r? `@oli-obk`
cc `@RalfJung`
---
LLVM can make use of the `noalias` parameter attribute on the parameter to `drop_in_place` in areas like argument promotion. Because the Rust compiler fully controls the code for `drop_in_place`, it can soundly deduce parameter attributes on it.
In #103957, Miri was changed to retag `drop_in_place`'s argument as if it was `&mut`, matching this change.
Deal with unnormalized projections when structurally resolving types with new solver
1. Normalize types in `structurally_resolved_type` when the new solver is enabled
2. Normalize built-in autoderef targets in `Autoderef` when the new solver is enabled
3. Normalize-erasing-regions in `resolve_type` in writeback
This is motivated by the UI test provided, which currently fails with:
```
error[E0609]: no field `x` on type `<usize as SliceIndex<[Foo]>>::Output`
--> <source>:9:11
|
9 | xs[0].x = 1;
| ^
```
I'm pretty happy with the approach in (1.) and (2.) and think we'll inevitably need something like this in the long-term, but (3.) seems like a hack to me. It's a *lot* of work to add tons of new calls to every user of these typeck results though (mir build, late lints, etc). Happy to discuss further.
r? `@lcnr`
This was added to control percentage sizes, in
79956b96e875e6ba2bfa551fabda6b7896f988ac
Now, the only percentage size is [`border-radius`], which is
based on the size of the box itself, not its containing block.
This leaves the property unused.
[`border-radius`]: https://developer.mozilla.org/en-US/docs/Web/CSS/border-radius
Give better error when collecting into `&[T]`
The detection of slice reference of `{integral}` in `rustc_on_unimplemented` is hacky, but a proper solution requires changing `FmtPrinter` to add a parameter to print integers as `{integral}` and I didn't want to change it just for `rustc_on_unimplemented`. I can do that if requested, though.
I'm open to better wording; this is the best I could come up with.
Mark internal functions and traits unsafe to reflect preconditions
No semantics are changed in this PR; I only mark some functions and and a trait `unsafe` which already had implicit preconditions. Although it seems somewhat redundant for `numfmt::Part::Copy` to contain a `&[u8]` instead of a `&str`, given that all of its current consumers ultimately expect valid UTF-8. Is the type also intended to work for byte-slice formatting in the future?
fix recursion depth handling after confirmation
fixes#111729
I think having to use `Obligation::with_depth` correctly everywhere is very hard because e.g. the nested obligations from `eq` currently do not have the correct obligation depth.
The new solver [completely removes `recursion_depth` from obligations](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/traits/solve/struct.Goal.html) and instead tracks the depth in the solver itself which is far easier to get right. Moving the old solver towards this shouldn't be that hard but is probably somewhat annoying.
r? `@matthewjasper`
Fix duplicate `arcinner_layout_for_value_layout` calls when using the uninit `Arc` constructors
What this fixes is the duplicate calls to `arcinner_layout_for_value_layout` seen here: https://godbolt.org/z/jr5Gxozhj
The issue was discovered alongside #111603 but is otherwise unrelated to the duplicate `alloca`s, which remain unsolved. Everything I tried to solve said main issue has failed.
As for the duplicate layout calculations, I also tried slapping `#[inline]` and `#[inline(always)]` on everything in sight but the only thing that worked in the end is to dedup the calls by hand.
Rather than returning an array of features from to_llvm_features, return a structure that contains
the dependencies. This also contains metadata on how the features depend on each other to allow for
the correct enabling and disabling.
Some features that are tied together only make sense to be folded
together when enabling the feature. For example on AArch64 sve and
neon are tied together, however it doesn't make sense to disable neon
when disabling sve.
In #91608 the fp-armv8 feature was removed as it's tied to the neon
feature. However disabling neon didn't actually disable the use of
floating point registers and instructions, for this `-fp-armv8` is
required.
