rust/compiler/rustc_codegen_llvm
bors 131a03664e Auto merge of #113040 - Kobzol:llvm-remark-streamer, r=tmiasko
Add `-Zremark-dir` unstable flag to write LLVM optimization remarks to YAML

This PR adds an option for `rustc` to emit LLVM optimization remarks to a set of YAML files, which can then be digested by existing tools, like https://github.com/OfekShilon/optview2. When `-Cremark-dir` is passed, and remarks are enabled (`-Cremark=all`), the remarks will be now written to the specified directory, **instead** of being printed to standard error output.  The files are named based on the CGU from which they are being generated.

Currently, the remarks are written using the LLVM streaming machinery, directly in the diagnostics handler. It seemed easier than going back to Rust and then form there back to C++ to use the streamer from the diagnostics handler. But there are many ways to implement this, of course, so I'm open to suggestions :)

I included some comments with questions into the code. Also, I'm not sure how to test this.

r? `@tmiasko`
2023-07-02 12:48:44 +00:00
..
src Auto merge of #113040 - Kobzol:llvm-remark-streamer, r=tmiasko 2023-07-02 12:48:44 +00:00
Cargo.toml use new c literals instead of cstr! macro 2023-05-31 19:40:24 +03:00
messages.ftl Use translatable diagnostics in rustc_const_eval 2023-06-01 14:45:18 +00:00
README.md mv compiler to compiler/ 2020-08-30 18:45:07 +03:00

The codegen crate contains the code to convert from MIR into LLVM IR, and then from LLVM IR into machine code. In general it contains code that runs towards the end of the compilation process.

For more information about how codegen works, see the rustc dev guide.