1 files changed, 733 insertions, 0 deletions
diff --git a/third_party/rust/itertools-0.8.0/benches/bench1.rs b/third_party/rust/itertools-0.8.0/benches/bench1.rs
new file mode 100644
index 0000000000..b9d3b4ff4b
--- /dev/null
+++ b/third_party/rust/itertools-0.8.0/benches/bench1.rs
@@ -0,0 +1,733 @@
+#![feature(test)]
+
+extern crate test;
+#[macro_use] extern crate itertools;
+
+use test::{black_box};
+use itertools::Itertools;
+
+use itertools::free::cloned;
+
+use std::iter::repeat;
+use std::cmp;
+use std::ops::Add;
+
+mod extra;
+
+use extra::ZipSlices;
+
+#[bench]
+fn slice_iter(b: &mut test::Bencher)
+{
+    let xs: Vec<_> = repeat(1i32).take(20).collect();
+    b.iter(|| for elt in xs.iter() {
+        test::black_box(elt);
+    })
+}
+
+#[bench]
+fn slice_iter_rev(b: &mut test::Bencher)
+{
+    let xs: Vec<_> = repeat(1i32).take(20).collect();
+    b.iter(|| for elt in xs.iter().rev() {
+        test::black_box(elt);
+    })
+}
+
+#[bench]
+fn zip_default_zip(b: &mut test::Bencher)
+{
+    let xs = vec![0; 1024];
+    let ys = vec![0; 768];
+    let xs = black_box(xs);
+    let ys = black_box(ys);
+
+    b.iter(|| {
+        for (&x, &y) in xs.iter().zip(&ys) {
+            test::black_box(x);
+            test::black_box(y);
+        }
+    })
+}
+
+#[bench]
+fn zipdot_i32_default_zip(b: &mut test::Bencher)
+{
+    let xs = vec![2; 1024];
+    let ys = vec![2; 768];
+    let xs = black_box(xs);
+    let ys = black_box(ys);
+
+    b.iter(|| {
+        let mut s = 0;
+        for (&x, &y) in xs.iter().zip(&ys) {
+            s += x * y;
+        }
+        s
+    })
+}
+
+#[bench]
+fn zipdot_f32_default_zip(b: &mut test::Bencher)
+{
+    let xs = vec![2f32; 1024];
+    let ys = vec![2f32; 768];
+    let xs = black_box(xs);
+    let ys = black_box(ys);
+
+    b.iter(|| {
+        let mut s = 0.;
+        for (&x, &y) in xs.iter().zip(&ys) {
+            s += x * y;
+        }
+        s
+    })
+}
+
+#[bench]
+fn zip_default_zip3(b: &mut test::Bencher)
+{
+    let xs = vec![0; 1024];
+    let ys = vec![0; 768];
+    let zs = vec![0; 766];
+    let xs = black_box(xs);
+    let ys = black_box(ys);
+    let zs = black_box(zs);
+
+    b.iter(|| {
+        for ((&x, &y), &z) in xs.iter().zip(&ys).zip(&zs) {
+            test::black_box(x);
+            test::black_box(y);
+            test::black_box(z);
+        }
+    })
+}
+
+#[bench]
+fn zip_slices_ziptuple(b: &mut test::Bencher)
+{
+    let xs = vec![0; 1024];
+    let ys = vec![0; 768];
+
+    b.iter(|| {
+        let xs = black_box(&xs);
+        let ys = black_box(&ys);
+        for (&x, &y) in itertools::multizip((xs, ys)) {
+            test::black_box(x);
+            test::black_box(y);
+        }
+    })
+}
+
+#[bench]
+fn zipslices(b: &mut test::Bencher)
+{
+    let xs = vec![0; 1024];
+    let ys = vec![0; 768];
+    let xs = black_box(xs);
+    let ys = black_box(ys);
+
+    b.iter(|| {
+        for (&x, &y) in ZipSlices::new(&xs, &ys) {
+            test::black_box(x);
+            test::black_box(y);
+        }
+    })
+}
+
+#[bench]
+fn zipslices_mut(b: &mut test::Bencher)
+{
+    let xs = vec![0; 1024];
+    let ys = vec![0; 768];
+    let xs = black_box(xs);
+    let mut ys = black_box(ys);
+
+    b.iter(|| {
+        for (&x, &mut y) in ZipSlices::from_slices(&xs[..], &mut ys[..]) {
+            test::black_box(x);
+            test::black_box(y);
+        }
+    })
+}
+
+#[bench]
+fn zipdot_i32_zipslices(b: &mut test::Bencher)
+{
+    let xs = vec![2; 1024];
+    let ys = vec![2; 768];
+    let xs = black_box(xs);
+    let ys = black_box(ys);
+
+    b.iter(|| {
+        let mut s = 0i32;
+        for (&x, &y) in ZipSlices::new(&xs, &ys) {
+            s += x * y;
+        }
+        s
+    })
+}
+
+#[bench]
+fn zipdot_f32_zipslices(b: &mut test::Bencher)
+{
+    let xs = vec![2f32; 1024];
+    let ys = vec![2f32; 768];
+    let xs = black_box(xs);
+    let ys = black_box(ys);
+
+    b.iter(|| {
+        let mut s = 0.;
+        for (&x, &y) in ZipSlices::new(&xs, &ys) {
+            s += x * y;
+        }
+        s
+    })
+}
+
+
+#[bench]
+fn zip_checked_counted_loop(b: &mut test::Bencher)
+{
+    let xs = vec![0; 1024];
+    let ys = vec![0; 768];
+    let xs = black_box(xs);
+    let ys = black_box(ys);
+
+    b.iter(|| {
+        // Must slice to equal lengths, and then bounds checks are eliminated!
+        let len = cmp::min(xs.len(), ys.len());
+        let xs = &xs[..len];
+        let ys = &ys[..len];
+
+        for i in 0..len {
+            let x = xs[i];
+            let y = ys[i];
+            test::black_box(x);
+            test::black_box(y);
+        }
+    })
+}
+
+#[bench]
+fn zipdot_i32_checked_counted_loop(b: &mut test::Bencher)
+{
+    let xs = vec![2; 1024];
+    let ys = vec![2; 768];
+    let xs = black_box(xs);
+    let ys = black_box(ys);
+
+    b.iter(|| {
+        // Must slice to equal lengths, and then bounds checks are eliminated!
+        let len = cmp::min(xs.len(), ys.len());
+        let xs = &xs[..len];
+        let ys = &ys[..len];
+
+        let mut s = 0i32;
+
+        for i in 0..len {
+            s += xs[i] * ys[i];
+        }
+        s
+    })
+}
+
+#[bench]
+fn zipdot_f32_checked_counted_loop(b: &mut test::Bencher)
+{
+    let xs = vec![2f32; 1024];
+    let ys = vec![2f32; 768];
+    let xs = black_box(xs);
+    let ys = black_box(ys);
+
+    b.iter(|| {
+        // Must slice to equal lengths, and then bounds checks are eliminated!
+        let len = cmp::min(xs.len(), ys.len());
+        let xs = &xs[..len];
+        let ys = &ys[..len];
+
+        let mut s = 0.;
+
+        for i in 0..len {
+            s += xs[i] * ys[i];
+        }
+        s
+    })
+}
+
+#[bench]
+fn zipdot_f32_checked_counted_unrolled_loop(b: &mut test::Bencher)
+{
+    let xs = vec![2f32; 1024];
+    let ys = vec![2f32; 768];
+    let xs = black_box(xs);
+    let ys = black_box(ys);
+
+    b.iter(|| {
+        // Must slice to equal lengths, and then bounds checks are eliminated!
+        let len = cmp::min(xs.len(), ys.len());
+        let mut xs = &xs[..len];
+        let mut ys = &ys[..len];
+
+        let mut s = 0.;
+        let (mut p0, mut p1, mut p2, mut p3, mut p4, mut p5, mut p6, mut p7) =
+            (0., 0., 0., 0., 0., 0., 0., 0.);
+
+        // how to unroll and have bounds checks eliminated (by cristicbz)
+        // split sum into eight parts to enable vectorization (by bluss)
+        while xs.len() >= 8 {
+            p0 += xs[0] * ys[0];
+            p1 += xs[1] * ys[1];
+            p2 += xs[2] * ys[2];
+            p3 += xs[3] * ys[3];
+            p4 += xs[4] * ys[4];
+            p5 += xs[5] * ys[5];
+            p6 += xs[6] * ys[6];
+            p7 += xs[7] * ys[7];
+
+            xs = &xs[8..];
+            ys = &ys[8..];
+        }
+        s += p0 + p4;
+        s += p1 + p5;
+        s += p2 + p6;
+        s += p3 + p7;
+
+        for i in 0..xs.len() {
+            s += xs[i] * ys[i];
+        }
+        s
+    })
+}
+
+#[bench]
+fn zip_unchecked_counted_loop(b: &mut test::Bencher)
+{
+    let xs = vec![0; 1024];
+    let ys = vec![0; 768];
+    let xs = black_box(xs);
+    let ys = black_box(ys);
+
+    b.iter(|| {
+        let len = cmp::min(xs.len(), ys.len());
+        for i in 0..len {
+            unsafe {
+            let x = *xs.get_unchecked(i);
+            let y = *ys.get_unchecked(i);
+            test::black_box(x);
+            test::black_box(y);
+            }
+        }
+    })
+}
+
+#[bench]
+fn zipdot_i32_unchecked_counted_loop(b: &mut test::Bencher)
+{
+    let xs = vec![2; 1024];
+    let ys = vec![2; 768];
+    let xs = black_box(xs);
+    let ys = black_box(ys);
+
+    b.iter(|| {
+        let len = cmp::min(xs.len(), ys.len());
+        let mut s = 0i32;
+        for i in 0..len {
+            unsafe {
+            let x = *xs.get_unchecked(i);
+            let y = *ys.get_unchecked(i);
+            s += x * y;
+            }
+        }
+        s
+    })
+}
+
+#[bench]
+fn zipdot_f32_unchecked_counted_loop(b: &mut test::Bencher)
+{
+    let xs = vec![2.; 1024];
+    let ys = vec![2.; 768];
+    let xs = black_box(xs);
+    let ys = black_box(ys);
+
+    b.iter(|| {
+        let len = cmp::min(xs.len(), ys.len());
+        let mut s = 0f32;
+        for i in 0..len {
+            unsafe {
+            let x = *xs.get_unchecked(i);
+            let y = *ys.get_unchecked(i);
+            s += x * y;
+            }
+        }
+        s
+    })
+}
+
+#[bench]
+fn zip_unchecked_counted_loop3(b: &mut test::Bencher)
+{
+    let xs = vec![0; 1024];
+    let ys = vec![0; 768];
+    let zs = vec![0; 766];
+    let xs = black_box(xs);
+    let ys = black_box(ys);
+    let zs = black_box(zs);
+
+    b.iter(|| {
+        let len = cmp::min(xs.len(), cmp::min(ys.len(), zs.len()));
+        for i in 0..len {
+            unsafe {
+            let x = *xs.get_unchecked(i);
+            let y = *ys.get_unchecked(i);
+            let z = *zs.get_unchecked(i);
+            test::black_box(x);
+            test::black_box(y);
+            test::black_box(z);
+            }
+        }
+    })
+}
+
+#[bench]
+fn group_by_lazy_1(b: &mut test::Bencher) {
+    let mut data = vec![0; 1024];
+    for (index, elt) in data.iter_mut().enumerate() {
+        *elt = index / 10;
+    }
+
+    let data = test::black_box(data);
+
+    b.iter(|| {
+        for (_key, group) in &data.iter().group_by(|elt| **elt) {
+            for elt in group {
+                test::black_box(elt);
+            }
+        }
+    })
+}
+
+#[bench]
+fn group_by_lazy_2(b: &mut test::Bencher) {
+    let mut data = vec![0; 1024];
+    for (index, elt) in data.iter_mut().enumerate() {
+        *elt = index / 2;
+    }
+
+    let data = test::black_box(data);
+
+    b.iter(|| {
+        for (_key, group) in &data.iter().group_by(|elt| **elt) {
+            for elt in group {
+                test::black_box(elt);
+            }
+        }
+    })
+}
+
+#[bench]
+fn slice_chunks(b: &mut test::Bencher) {
+    let data = vec![0; 1024];
+
+    let data = test::black_box(data);
+    let sz = test::black_box(10);
+
+    b.iter(|| {
+        for group in data.chunks(sz) {
+            for elt in group {
+                test::black_box(elt);
+            }
+        }
+    })
+}
+
+#[bench]
+fn chunks_lazy_1(b: &mut test::Bencher) {
+    let data = vec![0; 1024];
+
+    let data = test::black_box(data);
+    let sz = test::black_box(10);
+
+    b.iter(|| {
+        for group in &data.iter().chunks(sz) {
+            for elt in group {
+                test::black_box(elt);
+            }
+        }
+    })
+}
+
+#[bench]
+fn equal(b: &mut test::Bencher) {
+    let data = vec![7; 1024];
+    let l = data.len();
+    let alpha = test::black_box(&data[1..]);
+    let beta = test::black_box(&data[..l - 1]);
+    b.iter(|| {
+        itertools::equal(alpha, beta)
+    })
+}
+
+#[bench]
+fn merge_default(b: &mut test::Bencher) {
+    let mut data1 = vec![0; 1024];
+    let mut data2 = vec![0; 800];
+    let mut x = 0;
+    for (_, elt) in data1.iter_mut().enumerate() {
+        *elt = x;
+        x += 1;
+    }
+
+    let mut y = 0;
+    for (i, elt) in data2.iter_mut().enumerate() {
+        *elt += y;
+        if i % 3 == 0 {
+            y += 3;
+        } else {
+            y += 0;
+        }
+    }
+    let data1 = test::black_box(data1);
+    let data2 = test::black_box(data2);
+    b.iter(|| {
+        data1.iter().merge(&data2).count()
+    })
+}
+
+#[bench]
+fn merge_by_cmp(b: &mut test::Bencher) {
+    let mut data1 = vec![0; 1024];
+    let mut data2 = vec![0; 800];
+    let mut x = 0;
+    for (_, elt) in data1.iter_mut().enumerate() {
+        *elt = x;
+        x += 1;
+    }
+
+    let mut y = 0;
+    for (i, elt) in data2.iter_mut().enumerate() {
+        *elt += y;
+        if i % 3 == 0 {
+            y += 3;
+        } else {
+            y += 0;
+        }
+    }
+    let data1 = test::black_box(data1);
+    let data2 = test::black_box(data2);
+    b.iter(|| {
+        data1.iter().merge_by(&data2, PartialOrd::le).count()
+    })
+}
+
+#[bench]
+fn merge_by_lt(b: &mut test::Bencher) {
+    let mut data1 = vec![0; 1024];
+    let mut data2 = vec![0; 800];
+    let mut x = 0;
+    for (_, elt) in data1.iter_mut().enumerate() {
+        *elt = x;
+        x += 1;
+    }
+
+    let mut y = 0;
+    for (i, elt) in data2.iter_mut().enumerate() {
+        *elt += y;
+        if i % 3 == 0 {
+            y += 3;
+        } else {
+            y += 0;
+        }
+    }
+    let data1 = test::black_box(data1);
+    let data2 = test::black_box(data2);
+    b.iter(|| {
+        data1.iter().merge_by(&data2, |a, b| a <= b).count()
+    })
+}
+
+#[bench]
+fn kmerge_default(b: &mut test::Bencher) {
+    let mut data1 = vec![0; 1024];
+    let mut data2 = vec![0; 800];
+    let mut x = 0;
+    for (_, elt) in data1.iter_mut().enumerate() {
+        *elt = x;
+        x += 1;
+    }
+
+    let mut y = 0;
+    for (i, elt) in data2.iter_mut().enumerate() {
+        *elt += y;
+        if i % 3 == 0 {
+            y += 3;
+        } else {
+            y += 0;
+        }
+    }
+    let data1 = test::black_box(data1);
+    let data2 = test::black_box(data2);
+    let its = &[data1.iter(), data2.iter()];
+    b.iter(|| {
+        its.iter().cloned().kmerge().count()
+    })
+}
+
+#[bench]
+fn kmerge_tenway(b: &mut test::Bencher) {
+    let mut data = vec![0; 10240];
+
+    let mut state = 1729u16;
+    fn rng(state: &mut u16) -> u16 {
+        let new = state.wrapping_mul(31421) + 6927;
+        *state = new;
+        new
+    }
+
+    for elt in &mut data {
+        *elt = rng(&mut state);
+    }
+
+    let mut chunks = Vec::new();
+    let mut rest = &mut data[..];
+    while rest.len() > 0 {
+        let chunk_len = 1 + rng(&mut state) % 512;
+        let chunk_len = cmp::min(rest.len(), chunk_len as usize);
+        let (fst, tail) = {rest}.split_at_mut(chunk_len);
+        fst.sort();
+        chunks.push(fst.iter().cloned());
+        rest = tail;
+    }
+
+    // println!("Chunk lengths: {}", chunks.iter().format_with(", ", |elt, f| f(&elt.len())));
+
+    b.iter(|| {
+        chunks.iter().cloned().kmerge().count()
+    })
+}
+
+
+fn fast_integer_sum<I>(iter: I) -> I::Item
+    where I: IntoIterator,
+          I::Item: Default + Add<Output=I::Item>
+{
+    iter.into_iter().fold(<_>::default(), |x, y| x + y)
+}
+
+
+#[bench]
+fn step_vec_2(b: &mut test::Bencher) {
+    let v = vec![0; 1024];
+    b.iter(|| {
+        fast_integer_sum(cloned(v.iter().step(2)))
+    });
+}
+
+#[bench]
+fn step_vec_10(b: &mut test::Bencher) {
+    let v = vec![0; 1024];
+    b.iter(|| {
+        fast_integer_sum(cloned(v.iter().step(10)))
+    });
+}
+
+#[bench]
+fn step_range_2(b: &mut test::Bencher) {
+    let v = black_box(0..1024);
+    b.iter(|| {
+        fast_integer_sum(v.clone().step(2))
+    });
+}
+
+#[bench]
+fn step_range_10(b: &mut test::Bencher) {
+    let v = black_box(0..1024);
+    b.iter(|| {
+        fast_integer_sum(v.clone().step(10))
+    });
+}
+
+#[bench]
+fn cartesian_product_iterator(b: &mut test::Bencher)
+{
+    let xs = vec![0; 16];
+
+    b.iter(|| {
+        let mut sum = 0;
+        for (&x, &y, &z) in iproduct!(&xs, &xs, &xs) {
+            sum += x;
+            sum += y;
+            sum += z;
+        }
+        sum
+    })
+}
+
+#[bench]
+fn cartesian_product_fold(b: &mut test::Bencher)
+{
+    let xs = vec![0; 16];
+
+    b.iter(|| {
+        let mut sum = 0;
+        iproduct!(&xs, &xs, &xs).fold((), |(), (&x, &y, &z)| {
+            sum += x;
+            sum += y;
+            sum += z;
+        });
+        sum
+    })
+}
+
+#[bench]
+fn multi_cartesian_product_iterator(b: &mut test::Bencher)
+{
+    let xs = [vec![0; 16], vec![0; 16], vec![0; 16]];
+
+    b.iter(|| {
+        let mut sum = 0;
+        for x in xs.into_iter().multi_cartesian_product() {
+            sum += x[0];
+            sum += x[1];
+            sum += x[2];
+        }
+        sum
+    })
+}
+
+#[bench]
+fn multi_cartesian_product_fold(b: &mut test::Bencher)
+{
+    let xs = [vec![0; 16], vec![0; 16], vec![0; 16]];
+
+    b.iter(|| {
+        let mut sum = 0;
+        xs.into_iter().multi_cartesian_product().fold((), |(), x| {
+            sum += x[0];
+            sum += x[1];
+            sum += x[2];
+        });
+        sum
+    })
+}
+
+#[bench]
+fn cartesian_product_nested_for(b: &mut test::Bencher)
+{
+    let xs = vec![0; 16];
+
+    b.iter(|| {
+        let mut sum = 0;
+        for &x in &xs {
+            for &y in &xs {
+                for &z in &xs {
+                    sum += x;
+                    sum += y;
+                    sum += z;
+                }
+            }
+        }
+        sum
+    })
+}