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#![allow(unstable_name_collisions)]
use criterion::{criterion_group, criterion_main, Criterion};
use itertools::Itertools;
struct Unspecialized<I>(I);
impl<I> Iterator for Unspecialized<I>
where
I: Iterator,
{
type Item = I::Item;
#[inline(always)]
fn next(&mut self) -> Option<Self::Item> {
self.0.next()
}
#[inline(always)]
fn size_hint(&self) -> (usize, Option<usize>) {
self.0.size_hint()
}
}
mod specialization {
use super::*;
pub mod intersperse {
use super::*;
pub fn external(c: &mut Criterion) {
let arr = [1; 1024];
c.bench_function("external", move |b| {
b.iter(|| {
let mut sum = 0;
for &x in arr.iter().intersperse(&0) {
sum += x;
}
sum
})
});
}
pub fn internal_specialized(c: &mut Criterion) {
let arr = [1; 1024];
c.bench_function("internal specialized", move |b| {
b.iter(|| arr.iter().intersperse(&0).fold(0, |acc, x| acc + x))
});
}
pub fn internal_unspecialized(c: &mut Criterion) {
let arr = [1; 1024];
c.bench_function("internal unspecialized", move |b| {
b.iter(|| Unspecialized(arr.iter().intersperse(&0)).fold(0, |acc, x| acc + x))
});
}
}
}
criterion_group!(
benches,
specialization::intersperse::external,
specialization::intersperse::internal_specialized,
specialization::intersperse::internal_unspecialized,
);
criterion_main!(benches);
|
