mirror of
https://github.com/rust-lang/rust.git
synced 2024-11-22 14:55:26 +00:00
4ecfdfac51
Optimize `array::IntoIter` `.into_iter()` on arrays was slower than it needed to be (especially compared to slice iterator) since it uses `Range<usize>`, which needs to handle degenerate ranges like `10..4`. This PR adds an internal `IndexRange` type that's like `Range<usize>` but with a safety invariant that means it doesn't need to worry about those cases -- it only handles `start <= end` -- and thus can give LLVM more information to optimize better. I added one simple demonstration of the improvement as a codegen test. (`vec::IntoIter` uses pointers instead of indexes, so doesn't have this problem, but that only works because its elements are boxed. `array::IntoIter` can't use pointers because that would keep it from being movable.) |
||
---|---|---|
.. | ||
benches | ||
primitive_docs | ||
src | ||
tests | ||
Cargo.toml |