diff options
| author | Pietro Albini <pietro@pietroalbini.org> | 2018-08-01 21:46:37 +0200 |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2018-08-01 21:46:37 +0200 |
| commit | 6e7e3859c657ac35846e7337a35d407b7f9dffd8 (patch) | |
| tree | 7fc050f3df0ee7bc4be61b0d2084077418966363 /src/librustc_data_structures | |
| parent | eeb7b6ae093c666084bb0f35e73151dcbe7a93af (diff) | |
| parent | e462c06a280e4198b404323d7754e1308817b22e (diff) | |
| download | rust-6e7e3859c657ac35846e7337a35d407b7f9dffd8.tar.gz rust-6e7e3859c657ac35846e7337a35d407b7f9dffd8.zip | |
Rollup merge of #52942 - llogiq:smallvec-opt, r=Mark-Simulacrum
Another SmallVec.extend optimization This improves SmallVec.extend even more over #52859 while making the code easier to read. Before ``` test small_vec::tests::fill_small_vec_1_10_with_cap ... bench: 31 ns/iter (+/- 5) test small_vec::tests::fill_small_vec_1_10_wo_cap ... bench: 70 ns/iter (+/- 4) test small_vec::tests::fill_small_vec_1_50_with_cap ... bench: 36 ns/iter (+/- 3) test small_vec::tests::fill_small_vec_1_50_wo_cap ... bench: 256 ns/iter (+/- 17) test small_vec::tests::fill_small_vec_32_10_with_cap ... bench: 31 ns/iter (+/- 5) test small_vec::tests::fill_small_vec_32_10_wo_cap ... bench: 26 ns/iter (+/- 1) test small_vec::tests::fill_small_vec_32_50_with_cap ... bench: 49 ns/iter (+/- 4) test small_vec::tests::fill_small_vec_32_50_wo_cap ... bench: 219 ns/iter (+/- 11) test small_vec::tests::fill_small_vec_8_10_with_cap ... bench: 32 ns/iter (+/- 2) test small_vec::tests::fill_small_vec_8_10_wo_cap ... bench: 61 ns/iter (+/- 12) test small_vec::tests::fill_small_vec_8_50_with_cap ... bench: 37 ns/iter (+/- 3) test small_vec::tests::fill_small_vec_8_50_wo_cap ... bench: 210 ns/iter (+/- 10) ``` After: ``` test small_vec::tests::fill_small_vec_1_10_wo_cap ... bench: 31 ns/iter (+/- 3) test small_vec::tests::fill_small_vec_1_50_with_cap ... bench: 39 ns/iter (+/- 4) test small_vec::tests::fill_small_vec_1_50_wo_cap ... bench: 35 ns/iter (+/- 4) test small_vec::tests::fill_small_vec_32_10_with_cap ... bench: 37 ns/iter (+/- 3) test small_vec::tests::fill_small_vec_32_10_wo_cap ... bench: 32 ns/iter (+/- 2) test small_vec::tests::fill_small_vec_32_50_with_cap ... bench: 52 ns/iter (+/- 4) test small_vec::tests::fill_small_vec_32_50_wo_cap ... bench: 46 ns/iter (+/- 0) test small_vec::tests::fill_small_vec_8_10_with_cap ... bench: 35 ns/iter (+/- 4) test small_vec::tests::fill_small_vec_8_10_wo_cap ... bench: 31 ns/iter (+/- 0) test small_vec::tests::fill_small_vec_8_50_with_cap ... bench: 40 ns/iter (+/- 15) test small_vec::tests::fill_small_vec_8_50_wo_cap ... bench: 36 ns/iter (+/- 2) ```
Diffstat (limited to 'src/librustc_data_structures')
| -rw-r--r-- | src/librustc_data_structures/small_vec.rs | 17 |
1 files changed, 5 insertions, 12 deletions
diff --git a/src/librustc_data_structures/small_vec.rs b/src/librustc_data_structures/small_vec.rs index b5f52d54ae4..76b01beb4ba 100644 --- a/src/librustc_data_structures/small_vec.rs +++ b/src/librustc_data_structures/small_vec.rs @@ -169,18 +169,11 @@ impl<A: Array> FromIterator<A::Element> for SmallVec<A> { impl<A: Array> Extend<A::Element> for SmallVec<A> { fn extend<I: IntoIterator<Item=A::Element>>(&mut self, iter: I) { - if self.is_array() { - let iter = iter.into_iter(); - self.reserve(iter.size_hint().0); - - for el in iter { - self.push(el); - } - } else { - match self.0 { - AccumulateVec::Heap(ref mut vec) => vec.extend(iter), - _ => unreachable!() - } + let iter = iter.into_iter(); + self.reserve(iter.size_hint().0); + match self.0 { + AccumulateVec::Heap(ref mut vec) => vec.extend(iter), + _ => iter.for_each(|el| self.push(el)) } } } |