e1a632f136
Remove `DefId` from `EarlyParamRegion`
Currently we represent usages of `Region` parameters via the `ReEarlyParam` or `ReLateParam` variants. The `ReEarlyParam` is effectively equivalent to `TyKind::Param` and `ConstKind::Param` (i.e. it stores a `Symbol` and a `u32` index) however it also stores a `DefId` for the definition of the lifetime parameter.
This was used in roughly two places:
- Borrowck diagnostics instead of threading the appropriate `body_id` down to relevant locations. Interestingly there were already some places that had to pass down a `DefId` manually.
- Some opaque type checking logic was using the `DefId` field to track captured lifetimes
I've split this PR up into a commit for generate rote changes to diagnostics code to pass around a `DefId` manually everywhere, and another commit for the opaque type related changes which likely require more careful review as they might change the semantics of lints/errors.
Instead of manually passing the `DefId` around everywhere I previously tried to bundle it in with `TypeErrCtxt` but ran into issues with some call sites of `infcx.err_ctxt` being unable to provide a `DefId`, particularly places involved with trait solving and normalization. It might be worth investigating adding some new wrapper type to pass this around everywhere but I think this might be acceptable for now.
This pr also has the effect of reducing the size of `EarlyParamRegion` from 16 bytes -> 8 bytes. I wouldn't expect this to have any direct performance improvement however, other variants of `RegionKind` over `8` bytes are all because they contain a `BoundRegionKind` which is, as far as I know, mostly there for diagnostics. If we're ever able to remove this it would shrink the `RegionKind` type from `24` bytes to `12` (and with clever bit packing we might be able to get it to `8` bytes). I am curious what the performance impact would be of removing interning of `Region`'s if we ever manage to shrink `RegionKind` that much.
Sidenote: by removing the `DefId` the `Debug` output for `Region` has gotten significantly nicer. As an example see this opaque type debug print before vs after this PR:
`Opaque(DefId(0:13 ~ impl_trait_captures[aeb9]::foo::{opaque#0}), [DefId(0:9 ~ impl_trait_captures[aeb9]::foo::'a)_'a/#0, T, DefId(0:9 ~ impl_trait_captures[aeb9]::foo::'a)_'a/#0])`
`Opaque(DefId(0:13 ~ impl_trait_captures[aeb9]::foo::{opaque#0}), ['a/#0, T, 'a/#0])`
r? `@compiler-errors` (I would like someone who understands the opaque type setup to atleast review the type system commit, but the rest is likely reviewable by anyone)
|
||
|---|---|---|
| .cargo | ||
| .github | ||
| .vscode | ||
| assets | ||
| bench_data | ||
| crates | ||
| docs | ||
| editors/code | ||
| lib | ||
| xtask | ||
| .editorconfig | ||
| .git-blame-ignore-revs | ||
| .gitattributes | ||
| .gitignore | ||
| .typos.toml | ||
| Cargo.lock | ||
| Cargo.toml | ||
| clippy.toml | ||
| CONTRIBUTING.md | ||
| LICENSE-APACHE | ||
| LICENSE-MIT | ||
| PRIVACY.md | ||
| README.md | ||
| rust-bors.toml | ||
| rust-version | ||
| 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 check out the CONTRIBUTING.md or if you 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.