cac8464f0e
Ensure `ptr::read` gets all the same LLVM `load` metadata that dereferencing does I was looking into `array::IntoIter` optimization, and noticed that it wasn't annotating the loads with `noundef` for simple things like `array::IntoIter<i32, N>`. Trying to narrow it down, it seems that was because `MaybeUninit::assume_init_read` isn't marking the load as initialized (<https://rust.godbolt.org/z/Mxd8TPTnv>), which is unfortunate since that's basically its reason to exist. The root cause is that `ptr::read` is currently implemented via the *untyped* `copy_nonoverlapping`, and thus the `load` doesn't get any type-aware metadata: no `noundef`, no `!range`. This PR solves that by lowering `ptr::read(p)` to `copy *p` in MIR, for which the backends already do the right thing. Fortuitiously, this also improves the IR we give to LLVM for things like `mem::replace`, and fixes a couple of long-standing bugs where `ptr::read` on `Copy` types was worse than `*`ing them. Zulip conversation: <https://rust-lang.zulipchat.com/#narrow/stream/219381-t-libs/topic/Move.20array.3A.3AIntoIter.20to.20ManuallyDrop/near/341189936> cc `@erikdesjardins` `@JakobDegen` `@workingjubilee` `@the8472` Fixes #106369 Fixes #73258 |
||
|---|---|---|
| .cargo | ||
| .github | ||
| .vscode | ||
| assets | ||
| bench_data | ||
| crates | ||
| docs | ||
| editors/code | ||
| lib | ||
| xtask | ||
| .editorconfig | ||
| .git-blame-ignore-revs | ||
| .gitattributes | ||
| .gitignore | ||
| Cargo.lock | ||
| Cargo.toml | ||
| LICENSE-APACHE | ||
| LICENSE-MIT | ||
| PRIVACY.md | ||
| README.md | ||
| rustfmt.toml | ||
| triagebot.toml | ||
rust-analyzer is a modular compiler frontend for the Rust language. It is a part of a larger rls-2.0 effort to create excellent IDE support for Rust.
Quick Start
https://rust-analyzer.github.io/manual.html#installation
Documentation
If you want to contribute to rust-analyzer or are just curious about how things work under the hood, check the ./docs/dev folder.
If you want to use rust-analyzer's language server with your editor of choice, check the manual folder. It also contains some tips & tricks to help you be more productive when using rust-analyzer.
Security and Privacy
See the corresponding sections of the manual.
Communication
For usage and troubleshooting requests, please use "IDEs and Editors" category of the Rust forum:
https://users.rust-lang.org/c/ide/14
For questions about development and implementation, join rust-analyzer working group on Zulip:
https://rust-lang.zulipchat.com/#narrow/stream/185405-t-compiler.2Frust-analyzer
Quick Links
- Website: https://rust-analyzer.github.io/
- Metrics: https://rust-analyzer.github.io/metrics/
- API docs: https://rust-lang.github.io/rust-analyzer/ide/
- Changelog: https://rust-analyzer.github.io/thisweek
License
rust-analyzer is primarily distributed under the terms of both the MIT license and the Apache License (Version 2.0).
See LICENSE-APACHE and LICENSE-MIT for details.