255a4c58f5
Implement a generic Destination Propagation optimization on MIR This takes the work that was originally started by `@eddyb` in https://github.com/rust-lang/rust/pull/47954, and then explored by me in https://github.com/rust-lang/rust/pull/71003, and implements it in a general (ie. not limited to acyclic CFGs) and dataflow-driven way (so that no additional infrastructure in rustc is needed). The pass is configured to run at `mir-opt-level=2` and higher only. To enable it by default, some followup work on it is still needed: * Performance needs to be evaluated. I did some light optimization work and tested against `tuple-stress`, which caused trouble in my last attempt, but didn't go much in depth here. * We can also enable the pass only at `opt-level=2` and higher, if it is too slow to run in debug mode, but fine when optimizations run anyways. * Debuginfo needs to be fixed after locals are merged. I did not look into what is required for this. * Live ranges of locals (aka `StorageLive` and `StorageDead`) are currently deleted. We either need to decide that this is fine, or if not, merge the variable's live ranges (or remove these statements entirely – https://github.com/rust-lang/rust/issues/68622). Some benchmarks of the pass were done in https://github.com/rust-lang/rust/pull/72635. |
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| .. | ||
| bootstrap | ||
| build_helper | ||
| ci | ||
| doc | ||
| etc | ||
| librustdoc | ||
| llvm-project@833dd1e3d4 | ||
| test | ||
| tools | ||
| README.md | ||
| stage0.txt | ||
This directory contains the source code of the rust project, including:
- The test suite
- The bootstrapping build system
- Various submodules for tools, like rustdoc, rls, etc.
For more information on how various parts of the compiler work, see the rustc dev guide.