b0440d359b
The only instance of `ObligationForest` in use has an obligation type of `PendingPredicateObligation`, which contains a `PredicateObligation` and a `Vec<Ty>`. `FulfillmentContext::pending_obligations()` calls `ObligationForest::pending_obligations()`, which clones all the `PendingPredicateObligation`s. But the `Vec<Ty>` field of those cloned obligations is never touched. This patch changes `ObligationForest::pending_obligations()` to `map_pending_obligations` -- which gives callers control about which part of the obligation to clone -- and takes advantage of the change to avoid cloning the `Vec<Ty>`. The change speeds up runs of a few rustc-perf benchmarks, the best by 1%.
This directory contains the source code of the rust project, including:
rustcand its testslibstd- Various submodules for tools, like rustdoc, rls, etc.
For more information on how various parts of the compiler work, see the rustc guide.
Their is also useful content in the following READMEs, which are gradually being moved over to the guide:
- https://github.com/rust-lang/rust/tree/master/src/librustc/ty/maps
- https://github.com/rust-lang/rust/tree/master/src/librustc/dep_graph
- https://github.com/rust-lang/rust/blob/master/src/librustc/infer/region_constraints
- https://github.com/rust-lang/rust/tree/master/src/librustc/infer/higher_ranked
- https://github.com/rust-lang/rust/tree/master/src/librustc/infer/lexical_region_resolve