5496facb96
Use the same DISubprogram for each instance of the same inlined function within a caller # Issue Details: The call to `panic` within a function like `Option::unwrap` is translated to LLVM as a `tail call` (as it will never return), when multiple calls to the same function like this is inlined LLVM will notice the common `tail call` block (i.e., loading the same panic string + location info and then calling `panic`) and merge them together. When merging these instructions together, LLVM will also attempt to merge the debug locations as well, but this fails (i.e., debug info is dropped) as Rust emits a new `DISubprogram` at each inline site thus LLVM doesn't recognize that these are actually the same function and so thinks that there isn't a common debug location. As an example of this when building for x86_64 Windows (note the lack of `.cv_loc` before the call to `panic`, thus it will be attributed to the same line at the `addq` instruction): ``` .cv_loc 0 1 23 0 # src\lib.rs:23:0 addq $40, %rsp retq leaq .Lalloc_f570dea0a53168780ce9a91e67646421(%rip), %rcx leaq .Lalloc_629ace53b7e5b76aaa810d549cc84ea3(%rip), %r8 movl $43, %edx callq _ZN4core9panicking5panic17h12e60b9063f6dee8E int3 ``` # Fix Details: Cache the `DISubprogram` emitted for each inlined function instance within a caller so that this can be reused if that instance is encountered again, this also requires caching the `DILexicalBlock` and `DIVariable` objects to avoid creating duplicates. After this change the above assembly now looks like: ``` .cv_loc 0 1 23 0 # src\lib.rs:23:0 addq $40, %rsp retq .cv_inline_site_id 5 within 0 inlined_at 1 0 0 .cv_inline_site_id 6 within 5 inlined_at 1 12 0 .cv_loc 6 2 935 0 # library\core\src\option.rs:935:0 leaq .Lalloc_5f55955de67e57c79064b537689facea(%rip), %rcx leaq .Lalloc_e741d4de8cb5801e1fd7a6c6795c1559(%rip), %r8 movl $43, %edx callq _ZN4core9panicking5panic17hde1558f32d5b1c04E int3 ``` |
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| editors/code | ||
| lib | ||
| xtask | ||
| .editorconfig | ||
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| .gitignore | ||
| Cargo.lock | ||
| Cargo.toml | ||
| LICENSE-APACHE | ||
| LICENSE-MIT | ||
| PRIVACY.md | ||
| README.md | ||
| rustfmt.toml | ||
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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.