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-rw-r--r--library/alloc/benches/vec.rs784
1 files changed, 784 insertions, 0 deletions
diff --git a/library/alloc/benches/vec.rs b/library/alloc/benches/vec.rs
new file mode 100644
index 000000000..663f6b9dd
--- /dev/null
+++ b/library/alloc/benches/vec.rs
@@ -0,0 +1,784 @@
+use rand::RngCore;
+use std::iter::{repeat, FromIterator};
+use test::{black_box, Bencher};
+
+#[bench]
+fn bench_new(b: &mut Bencher) {
+ b.iter(|| Vec::<u32>::new())
+}
+
+fn do_bench_with_capacity(b: &mut Bencher, src_len: usize) {
+ b.bytes = src_len as u64;
+
+ b.iter(|| Vec::<u32>::with_capacity(src_len))
+}
+
+#[bench]
+fn bench_with_capacity_0000(b: &mut Bencher) {
+ do_bench_with_capacity(b, 0)
+}
+
+#[bench]
+fn bench_with_capacity_0010(b: &mut Bencher) {
+ do_bench_with_capacity(b, 10)
+}
+
+#[bench]
+fn bench_with_capacity_0100(b: &mut Bencher) {
+ do_bench_with_capacity(b, 100)
+}
+
+#[bench]
+fn bench_with_capacity_1000(b: &mut Bencher) {
+ do_bench_with_capacity(b, 1000)
+}
+
+fn do_bench_from_fn(b: &mut Bencher, src_len: usize) {
+ b.bytes = src_len as u64;
+
+ b.iter(|| (0..src_len).collect::<Vec<_>>())
+}
+
+#[bench]
+fn bench_from_fn_0000(b: &mut Bencher) {
+ do_bench_from_fn(b, 0)
+}
+
+#[bench]
+fn bench_from_fn_0010(b: &mut Bencher) {
+ do_bench_from_fn(b, 10)
+}
+
+#[bench]
+fn bench_from_fn_0100(b: &mut Bencher) {
+ do_bench_from_fn(b, 100)
+}
+
+#[bench]
+fn bench_from_fn_1000(b: &mut Bencher) {
+ do_bench_from_fn(b, 1000)
+}
+
+fn do_bench_from_elem(b: &mut Bencher, src_len: usize) {
+ b.bytes = src_len as u64;
+
+ b.iter(|| repeat(5).take(src_len).collect::<Vec<usize>>())
+}
+
+#[bench]
+fn bench_from_elem_0000(b: &mut Bencher) {
+ do_bench_from_elem(b, 0)
+}
+
+#[bench]
+fn bench_from_elem_0010(b: &mut Bencher) {
+ do_bench_from_elem(b, 10)
+}
+
+#[bench]
+fn bench_from_elem_0100(b: &mut Bencher) {
+ do_bench_from_elem(b, 100)
+}
+
+#[bench]
+fn bench_from_elem_1000(b: &mut Bencher) {
+ do_bench_from_elem(b, 1000)
+}
+
+fn do_bench_from_slice(b: &mut Bencher, src_len: usize) {
+ let src: Vec<_> = FromIterator::from_iter(0..src_len);
+
+ b.bytes = src_len as u64;
+
+ b.iter(|| src.as_slice().to_vec());
+}
+
+#[bench]
+fn bench_from_slice_0000(b: &mut Bencher) {
+ do_bench_from_slice(b, 0)
+}
+
+#[bench]
+fn bench_from_slice_0010(b: &mut Bencher) {
+ do_bench_from_slice(b, 10)
+}
+
+#[bench]
+fn bench_from_slice_0100(b: &mut Bencher) {
+ do_bench_from_slice(b, 100)
+}
+
+#[bench]
+fn bench_from_slice_1000(b: &mut Bencher) {
+ do_bench_from_slice(b, 1000)
+}
+
+fn do_bench_from_iter(b: &mut Bencher, src_len: usize) {
+ let src: Vec<_> = FromIterator::from_iter(0..src_len);
+
+ b.bytes = src_len as u64;
+
+ b.iter(|| {
+ let dst: Vec<_> = FromIterator::from_iter(src.iter().cloned());
+ dst
+ });
+}
+
+#[bench]
+fn bench_from_iter_0000(b: &mut Bencher) {
+ do_bench_from_iter(b, 0)
+}
+
+#[bench]
+fn bench_from_iter_0010(b: &mut Bencher) {
+ do_bench_from_iter(b, 10)
+}
+
+#[bench]
+fn bench_from_iter_0100(b: &mut Bencher) {
+ do_bench_from_iter(b, 100)
+}
+
+#[bench]
+fn bench_from_iter_1000(b: &mut Bencher) {
+ do_bench_from_iter(b, 1000)
+}
+
+fn do_bench_extend(b: &mut Bencher, dst_len: usize, src_len: usize) {
+ let dst: Vec<_> = FromIterator::from_iter(0..dst_len);
+ let src: Vec<_> = FromIterator::from_iter(dst_len..dst_len + src_len);
+
+ b.bytes = src_len as u64;
+
+ b.iter(|| {
+ let mut dst = dst.clone();
+ dst.extend(src.clone());
+ dst
+ });
+}
+
+#[bench]
+fn bench_extend_0000_0000(b: &mut Bencher) {
+ do_bench_extend(b, 0, 0)
+}
+
+#[bench]
+fn bench_extend_0000_0010(b: &mut Bencher) {
+ do_bench_extend(b, 0, 10)
+}
+
+#[bench]
+fn bench_extend_0000_0100(b: &mut Bencher) {
+ do_bench_extend(b, 0, 100)
+}
+
+#[bench]
+fn bench_extend_0000_1000(b: &mut Bencher) {
+ do_bench_extend(b, 0, 1000)
+}
+
+#[bench]
+fn bench_extend_0010_0010(b: &mut Bencher) {
+ do_bench_extend(b, 10, 10)
+}
+
+#[bench]
+fn bench_extend_0100_0100(b: &mut Bencher) {
+ do_bench_extend(b, 100, 100)
+}
+
+#[bench]
+fn bench_extend_1000_1000(b: &mut Bencher) {
+ do_bench_extend(b, 1000, 1000)
+}
+
+fn do_bench_extend_from_slice(b: &mut Bencher, dst_len: usize, src_len: usize) {
+ let dst: Vec<_> = FromIterator::from_iter(0..dst_len);
+ let src: Vec<_> = FromIterator::from_iter(dst_len..dst_len + src_len);
+
+ b.bytes = src_len as u64;
+
+ b.iter(|| {
+ let mut dst = dst.clone();
+ dst.extend_from_slice(&src);
+ dst
+ });
+}
+
+#[bench]
+fn bench_extend_recycle(b: &mut Bencher) {
+ let mut data = vec![0; 1000];
+
+ b.iter(|| {
+ let tmp = std::mem::take(&mut data);
+ let mut to_extend = black_box(Vec::new());
+ to_extend.extend(tmp.into_iter());
+ data = black_box(to_extend);
+ });
+
+ black_box(data);
+}
+
+#[bench]
+fn bench_extend_from_slice_0000_0000(b: &mut Bencher) {
+ do_bench_extend_from_slice(b, 0, 0)
+}
+
+#[bench]
+fn bench_extend_from_slice_0000_0010(b: &mut Bencher) {
+ do_bench_extend_from_slice(b, 0, 10)
+}
+
+#[bench]
+fn bench_extend_from_slice_0000_0100(b: &mut Bencher) {
+ do_bench_extend_from_slice(b, 0, 100)
+}
+
+#[bench]
+fn bench_extend_from_slice_0000_1000(b: &mut Bencher) {
+ do_bench_extend_from_slice(b, 0, 1000)
+}
+
+#[bench]
+fn bench_extend_from_slice_0010_0010(b: &mut Bencher) {
+ do_bench_extend_from_slice(b, 10, 10)
+}
+
+#[bench]
+fn bench_extend_from_slice_0100_0100(b: &mut Bencher) {
+ do_bench_extend_from_slice(b, 100, 100)
+}
+
+#[bench]
+fn bench_extend_from_slice_1000_1000(b: &mut Bencher) {
+ do_bench_extend_from_slice(b, 1000, 1000)
+}
+
+fn do_bench_clone(b: &mut Bencher, src_len: usize) {
+ let src: Vec<usize> = FromIterator::from_iter(0..src_len);
+
+ b.bytes = src_len as u64;
+
+ b.iter(|| src.clone());
+}
+
+#[bench]
+fn bench_clone_0000(b: &mut Bencher) {
+ do_bench_clone(b, 0)
+}
+
+#[bench]
+fn bench_clone_0010(b: &mut Bencher) {
+ do_bench_clone(b, 10)
+}
+
+#[bench]
+fn bench_clone_0100(b: &mut Bencher) {
+ do_bench_clone(b, 100)
+}
+
+#[bench]
+fn bench_clone_1000(b: &mut Bencher) {
+ do_bench_clone(b, 1000)
+}
+
+fn do_bench_clone_from(b: &mut Bencher, times: usize, dst_len: usize, src_len: usize) {
+ let dst: Vec<_> = FromIterator::from_iter(0..src_len);
+ let src: Vec<_> = FromIterator::from_iter(dst_len..dst_len + src_len);
+
+ b.bytes = (times * src_len) as u64;
+
+ b.iter(|| {
+ let mut dst = dst.clone();
+
+ for _ in 0..times {
+ dst.clone_from(&src);
+ dst = black_box(dst);
+ }
+ dst
+ });
+}
+
+#[bench]
+fn bench_clone_from_01_0000_0000(b: &mut Bencher) {
+ do_bench_clone_from(b, 1, 0, 0)
+}
+
+#[bench]
+fn bench_clone_from_01_0000_0010(b: &mut Bencher) {
+ do_bench_clone_from(b, 1, 0, 10)
+}
+
+#[bench]
+fn bench_clone_from_01_0000_0100(b: &mut Bencher) {
+ do_bench_clone_from(b, 1, 0, 100)
+}
+
+#[bench]
+fn bench_clone_from_01_0000_1000(b: &mut Bencher) {
+ do_bench_clone_from(b, 1, 0, 1000)
+}
+
+#[bench]
+fn bench_clone_from_01_0010_0010(b: &mut Bencher) {
+ do_bench_clone_from(b, 1, 10, 10)
+}
+
+#[bench]
+fn bench_clone_from_01_0100_0100(b: &mut Bencher) {
+ do_bench_clone_from(b, 1, 100, 100)
+}
+
+#[bench]
+fn bench_clone_from_01_1000_1000(b: &mut Bencher) {
+ do_bench_clone_from(b, 1, 1000, 1000)
+}
+
+#[bench]
+fn bench_clone_from_01_0010_0100(b: &mut Bencher) {
+ do_bench_clone_from(b, 1, 10, 100)
+}
+
+#[bench]
+fn bench_clone_from_01_0100_1000(b: &mut Bencher) {
+ do_bench_clone_from(b, 1, 100, 1000)
+}
+
+#[bench]
+fn bench_clone_from_01_0010_0000(b: &mut Bencher) {
+ do_bench_clone_from(b, 1, 10, 0)
+}
+
+#[bench]
+fn bench_clone_from_01_0100_0010(b: &mut Bencher) {
+ do_bench_clone_from(b, 1, 100, 10)
+}
+
+#[bench]
+fn bench_clone_from_01_1000_0100(b: &mut Bencher) {
+ do_bench_clone_from(b, 1, 1000, 100)
+}
+
+#[bench]
+fn bench_clone_from_10_0000_0000(b: &mut Bencher) {
+ do_bench_clone_from(b, 10, 0, 0)
+}
+
+#[bench]
+fn bench_clone_from_10_0000_0010(b: &mut Bencher) {
+ do_bench_clone_from(b, 10, 0, 10)
+}
+
+#[bench]
+fn bench_clone_from_10_0000_0100(b: &mut Bencher) {
+ do_bench_clone_from(b, 10, 0, 100)
+}
+
+#[bench]
+fn bench_clone_from_10_0000_1000(b: &mut Bencher) {
+ do_bench_clone_from(b, 10, 0, 1000)
+}
+
+#[bench]
+fn bench_clone_from_10_0010_0010(b: &mut Bencher) {
+ do_bench_clone_from(b, 10, 10, 10)
+}
+
+#[bench]
+fn bench_clone_from_10_0100_0100(b: &mut Bencher) {
+ do_bench_clone_from(b, 10, 100, 100)
+}
+
+#[bench]
+fn bench_clone_from_10_1000_1000(b: &mut Bencher) {
+ do_bench_clone_from(b, 10, 1000, 1000)
+}
+
+#[bench]
+fn bench_clone_from_10_0010_0100(b: &mut Bencher) {
+ do_bench_clone_from(b, 10, 10, 100)
+}
+
+#[bench]
+fn bench_clone_from_10_0100_1000(b: &mut Bencher) {
+ do_bench_clone_from(b, 10, 100, 1000)
+}
+
+#[bench]
+fn bench_clone_from_10_0010_0000(b: &mut Bencher) {
+ do_bench_clone_from(b, 10, 10, 0)
+}
+
+#[bench]
+fn bench_clone_from_10_0100_0010(b: &mut Bencher) {
+ do_bench_clone_from(b, 10, 100, 10)
+}
+
+#[bench]
+fn bench_clone_from_10_1000_0100(b: &mut Bencher) {
+ do_bench_clone_from(b, 10, 1000, 100)
+}
+
+macro_rules! bench_in_place {
+ ($($fname:ident, $type:ty, $count:expr, $init:expr);*) => {
+ $(
+ #[bench]
+ fn $fname(b: &mut Bencher) {
+ b.iter(|| {
+ let src: Vec<$type> = black_box(vec![$init; $count]);
+ src.into_iter()
+ .enumerate()
+ .map(|(idx, e)| idx as $type ^ e)
+ .collect::<Vec<$type>>()
+ });
+ }
+ )+
+ };
+}
+
+bench_in_place![
+ bench_in_place_xxu8_0010_i0, u8, 10, 0;
+ bench_in_place_xxu8_0100_i0, u8, 100, 0;
+ bench_in_place_xxu8_1000_i0, u8, 1000, 0;
+ bench_in_place_xxu8_0010_i1, u8, 10, 1;
+ bench_in_place_xxu8_0100_i1, u8, 100, 1;
+ bench_in_place_xxu8_1000_i1, u8, 1000, 1;
+ bench_in_place_xu32_0010_i0, u32, 10, 0;
+ bench_in_place_xu32_0100_i0, u32, 100, 0;
+ bench_in_place_xu32_1000_i0, u32, 1000, 0;
+ bench_in_place_xu32_0010_i1, u32, 10, 1;
+ bench_in_place_xu32_0100_i1, u32, 100, 1;
+ bench_in_place_xu32_1000_i1, u32, 1000, 1;
+ bench_in_place_u128_0010_i0, u128, 10, 0;
+ bench_in_place_u128_0100_i0, u128, 100, 0;
+ bench_in_place_u128_1000_i0, u128, 1000, 0;
+ bench_in_place_u128_0010_i1, u128, 10, 1;
+ bench_in_place_u128_0100_i1, u128, 100, 1;
+ bench_in_place_u128_1000_i1, u128, 1000, 1
+];
+
+#[bench]
+fn bench_in_place_recycle(b: &mut Bencher) {
+ let mut data = vec![0; 1000];
+
+ b.iter(|| {
+ let tmp = std::mem::take(&mut data);
+ data = black_box(
+ tmp.into_iter()
+ .enumerate()
+ .map(|(idx, e)| idx.wrapping_add(e))
+ .fuse()
+ .collect::<Vec<usize>>(),
+ );
+ });
+}
+
+#[bench]
+fn bench_in_place_zip_recycle(b: &mut Bencher) {
+ let mut data = vec![0u8; 1000];
+ let mut rng = crate::bench_rng();
+ let mut subst = vec![0u8; 1000];
+ rng.fill_bytes(&mut subst[..]);
+
+ b.iter(|| {
+ let tmp = std::mem::take(&mut data);
+ let mangled = tmp
+ .into_iter()
+ .zip(subst.iter().copied())
+ .enumerate()
+ .map(|(i, (d, s))| d.wrapping_add(i as u8) ^ s)
+ .collect::<Vec<_>>();
+ data = black_box(mangled);
+ });
+}
+
+#[bench]
+fn bench_in_place_zip_iter_mut(b: &mut Bencher) {
+ let mut data = vec![0u8; 256];
+ let mut rng = crate::bench_rng();
+ let mut subst = vec![0u8; 1000];
+ rng.fill_bytes(&mut subst[..]);
+
+ b.iter(|| {
+ data.iter_mut().enumerate().for_each(|(i, d)| {
+ *d = d.wrapping_add(i as u8) ^ subst[i];
+ });
+ });
+
+ black_box(data);
+}
+
+pub fn vec_cast<T, U>(input: Vec<T>) -> Vec<U> {
+ input.into_iter().map(|e| unsafe { std::mem::transmute_copy(&e) }).collect()
+}
+
+#[bench]
+fn bench_transmute(b: &mut Bencher) {
+ let mut vec = vec![10u32; 100];
+ b.bytes = 800; // 2 casts x 4 bytes x 100
+ b.iter(|| {
+ let v = std::mem::take(&mut vec);
+ let v = black_box(vec_cast::<u32, i32>(v));
+ let v = black_box(vec_cast::<i32, u32>(v));
+ vec = v;
+ });
+}
+
+#[derive(Clone)]
+struct Droppable(usize);
+
+impl Drop for Droppable {
+ fn drop(&mut self) {
+ black_box(self);
+ }
+}
+
+#[bench]
+fn bench_in_place_collect_droppable(b: &mut Bencher) {
+ let v: Vec<Droppable> = std::iter::repeat_with(|| Droppable(0)).take(1000).collect();
+ b.iter(|| {
+ v.clone()
+ .into_iter()
+ .skip(100)
+ .enumerate()
+ .map(|(i, e)| Droppable(i ^ e.0))
+ .collect::<Vec<_>>()
+ })
+}
+
+const LEN: usize = 16384;
+
+#[bench]
+fn bench_chain_collect(b: &mut Bencher) {
+ let data = black_box([0; LEN]);
+ b.iter(|| data.iter().cloned().chain([1]).collect::<Vec<_>>());
+}
+
+#[bench]
+fn bench_chain_chain_collect(b: &mut Bencher) {
+ let data = black_box([0; LEN]);
+ b.iter(|| data.iter().cloned().chain([1]).chain([2]).collect::<Vec<_>>());
+}
+
+#[bench]
+fn bench_nest_chain_chain_collect(b: &mut Bencher) {
+ let data = black_box([0; LEN]);
+ b.iter(|| {
+ data.iter().cloned().chain([1].iter().chain([2].iter()).cloned()).collect::<Vec<_>>()
+ });
+}
+
+#[bench]
+fn bench_range_map_collect(b: &mut Bencher) {
+ b.iter(|| (0..LEN).map(|_| u32::default()).collect::<Vec<_>>());
+}
+
+#[bench]
+fn bench_chain_extend_ref(b: &mut Bencher) {
+ let data = black_box([0; LEN]);
+ b.iter(|| {
+ let mut v = Vec::<u32>::with_capacity(data.len() + 1);
+ v.extend(data.iter().chain([1].iter()));
+ v
+ });
+}
+
+#[bench]
+fn bench_chain_extend_value(b: &mut Bencher) {
+ let data = black_box([0; LEN]);
+ b.iter(|| {
+ let mut v = Vec::<u32>::with_capacity(data.len() + 1);
+ v.extend(data.iter().cloned().chain(Some(1)));
+ v
+ });
+}
+
+#[bench]
+fn bench_rev_1(b: &mut Bencher) {
+ let data = black_box([0; LEN]);
+ b.iter(|| {
+ let mut v = Vec::<u32>::new();
+ v.extend(data.iter().rev());
+ v
+ });
+}
+
+#[bench]
+fn bench_rev_2(b: &mut Bencher) {
+ let data = black_box([0; LEN]);
+ b.iter(|| {
+ let mut v = Vec::<u32>::with_capacity(data.len());
+ v.extend(data.iter().rev());
+ v
+ });
+}
+
+#[bench]
+fn bench_map_regular(b: &mut Bencher) {
+ let data = black_box([(0, 0); LEN]);
+ b.iter(|| {
+ let mut v = Vec::<u32>::new();
+ v.extend(data.iter().map(|t| t.1));
+ v
+ });
+}
+
+#[bench]
+fn bench_map_fast(b: &mut Bencher) {
+ let data = black_box([(0, 0); LEN]);
+ b.iter(|| {
+ let mut result: Vec<u32> = Vec::with_capacity(data.len());
+ for i in 0..data.len() {
+ unsafe {
+ *result.as_mut_ptr().add(i) = data[i].0;
+ result.set_len(i);
+ }
+ }
+ result
+ });
+}
+
+fn random_sorted_fill(mut seed: u32, buf: &mut [u32]) {
+ let mask = if buf.len() < 8192 {
+ 0xFF
+ } else if buf.len() < 200_000 {
+ 0xFFFF
+ } else {
+ 0xFFFF_FFFF
+ };
+
+ for item in buf.iter_mut() {
+ seed ^= seed << 13;
+ seed ^= seed >> 17;
+ seed ^= seed << 5;
+
+ *item = seed & mask;
+ }
+
+ buf.sort();
+}
+
+fn bench_vec_dedup_old(b: &mut Bencher, sz: usize) {
+ let mut template = vec![0u32; sz];
+ b.bytes = std::mem::size_of_val(template.as_slice()) as u64;
+ random_sorted_fill(0x43, &mut template);
+
+ let mut vec = template.clone();
+ b.iter(|| {
+ let len = {
+ let (dedup, _) = vec.partition_dedup();
+ dedup.len()
+ };
+ vec.truncate(len);
+
+ black_box(vec.first());
+ vec.clear();
+ vec.extend_from_slice(&template);
+ });
+}
+
+fn bench_vec_dedup_new(b: &mut Bencher, sz: usize) {
+ let mut template = vec![0u32; sz];
+ b.bytes = std::mem::size_of_val(template.as_slice()) as u64;
+ random_sorted_fill(0x43, &mut template);
+
+ let mut vec = template.clone();
+ b.iter(|| {
+ vec.dedup();
+ black_box(vec.first());
+ vec.clear();
+ vec.extend_from_slice(&template);
+ });
+}
+
+#[bench]
+fn bench_dedup_old_100(b: &mut Bencher) {
+ bench_vec_dedup_old(b, 100);
+}
+#[bench]
+fn bench_dedup_new_100(b: &mut Bencher) {
+ bench_vec_dedup_new(b, 100);
+}
+
+#[bench]
+fn bench_dedup_old_1000(b: &mut Bencher) {
+ bench_vec_dedup_old(b, 1000);
+}
+#[bench]
+fn bench_dedup_new_1000(b: &mut Bencher) {
+ bench_vec_dedup_new(b, 1000);
+}
+
+#[bench]
+fn bench_dedup_old_10000(b: &mut Bencher) {
+ bench_vec_dedup_old(b, 10000);
+}
+#[bench]
+fn bench_dedup_new_10000(b: &mut Bencher) {
+ bench_vec_dedup_new(b, 10000);
+}
+
+#[bench]
+fn bench_dedup_old_100000(b: &mut Bencher) {
+ bench_vec_dedup_old(b, 100000);
+}
+#[bench]
+fn bench_dedup_new_100000(b: &mut Bencher) {
+ bench_vec_dedup_new(b, 100000);
+}
+
+#[bench]
+fn bench_flat_map_collect(b: &mut Bencher) {
+ let v = vec![777u32; 500000];
+ b.iter(|| v.iter().flat_map(|color| color.rotate_left(8).to_be_bytes()).collect::<Vec<_>>());
+}
+
+/// Reference benchmark that `retain` has to compete with.
+#[bench]
+fn bench_retain_iter_100000(b: &mut Bencher) {
+ let mut v = Vec::with_capacity(100000);
+
+ b.iter(|| {
+ let mut tmp = std::mem::take(&mut v);
+ tmp.clear();
+ tmp.extend(black_box(1..=100000));
+ v = tmp.into_iter().filter(|x| x & 1 == 0).collect();
+ });
+}
+
+#[bench]
+fn bench_retain_100000(b: &mut Bencher) {
+ let mut v = Vec::with_capacity(100000);
+
+ b.iter(|| {
+ v.clear();
+ v.extend(black_box(1..=100000));
+ v.retain(|x| x & 1 == 0)
+ });
+}
+
+#[bench]
+fn bench_retain_whole_100000(b: &mut Bencher) {
+ let mut v = black_box(vec![826u32; 100000]);
+ b.iter(|| v.retain(|x| *x == 826u32));
+}
+
+#[bench]
+fn bench_next_chunk(b: &mut Bencher) {
+ let v = vec![13u8; 2048];
+
+ b.iter(|| {
+ const CHUNK: usize = 8;
+
+ let mut sum = [0u32; CHUNK];
+ let mut iter = black_box(v.clone()).into_iter();
+
+ while let Ok(chunk) = iter.next_chunk::<CHUNK>() {
+ for i in 0..CHUNK {
+ sum[i] += chunk[i] as u32;
+ }
+ }
+
+ sum
+ })
+}