Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Improve tests and benchmarks for slice::sort and slice::sort_unstable #42882

Merged
merged 2 commits into from Jul 1, 2017
Merged

Improve tests and benchmarks for slice::sort and slice::sort_unstable #42882

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
12205f1
Improve sort tests and benchmarks
Jun 24, 2017
723833f
Move thread_rng() outside the loop
Jun 26, 2017
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
1 change: 1 addition & 0 deletions src/liballoc/benches/lib.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -17,6 +17,7 @@
#![feature(sort_unstable)]
#![feature(test)]

extern crate rand;
extern crate test;

mod btree;
Expand Down
54 changes: 35 additions & 19 deletions src/liballoc/benches/slice.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -8,9 +8,11 @@
// option. This file may not be copied, modified, or distributed
// except according to those terms.

use std::{mem, ptr};
use std::__rand::{Rng, thread_rng};
use std::__rand::{thread_rng};
use std::mem;
use std::ptr;

use rand::{Rng, SeedableRng, XorShiftRng};
use test::{Bencher, black_box};

#[bench]
Expand Down Expand Up @@ -191,17 +193,17 @@ fn gen_descending(len: usize) -> Vec<u64> {
}

fn gen_random(len: usize) -> Vec<u64> {
let mut rng = thread_rng();
let mut rng = XorShiftRng::from_seed([0, 1, 2, 3]);
rng.gen_iter::<u64>().take(len).collect()
}

fn gen_random_bytes(len: usize) -> Vec<u8> {
let mut rng = thread_rng();
let mut rng = XorShiftRng::from_seed([0, 1, 2, 3]);
rng.gen_iter::<u8>().take(len).collect()
}

fn gen_mostly_ascending(len: usize) -> Vec<u64> {
let mut rng = thread_rng();
let mut rng = XorShiftRng::from_seed([0, 1, 2, 3]);
let mut v = gen_ascending(len);
for _ in (0usize..).take_while(|x| x * x <= len) {
let x = rng.gen::<usize>() % len;
Expand All @@ -212,7 +214,7 @@ fn gen_mostly_ascending(len: usize) -> Vec<u64> {
}

fn gen_mostly_descending(len: usize) -> Vec<u64> {
let mut rng = thread_rng();
let mut rng = XorShiftRng::from_seed([0, 1, 2, 3]);
let mut v = gen_descending(len);
for _ in (0usize..).take_while(|x| x * x <= len) {
let x = rng.gen::<usize>() % len;
Expand All @@ -223,7 +225,7 @@ fn gen_mostly_descending(len: usize) -> Vec<u64> {
}

fn gen_strings(len: usize) -> Vec<String> {
let mut rng = thread_rng();
let mut rng = XorShiftRng::from_seed([0, 1, 2, 3]);
let mut v = vec![];
for _ in 0..len {
let n = rng.gen::<usize>() % 20 + 1;
Expand All @@ -233,26 +235,40 @@ fn gen_strings(len: usize) -> Vec<String> {
}

fn gen_big_random(len: usize) -> Vec<[u64; 16]> {
let mut rng = thread_rng();
let mut rng = XorShiftRng::from_seed([0, 1, 2, 3]);
rng.gen_iter().map(|x| [x; 16]).take(len).collect()
}

macro_rules! sort {
($f:ident, $name:ident, $gen:expr, $len:expr) => {
#[bench]
fn $name(b: &mut Bencher) {
b.iter(|| $gen($len).$f());
let v = $gen($len);
b.iter(|| v.clone().$f());
b.bytes = $len * mem::size_of_val(&$gen(1)[0]) as u64;
}
}
}

macro_rules! sort_strings {
($f:ident, $name:ident, $gen:expr, $len:expr) => {
#[bench]
fn $name(b: &mut Bencher) {
let v = $gen($len);
let v = v.iter().map(|s| &**s).collect::<Vec<&str>>();
b.iter(|| v.clone().$f());
b.bytes = $len * mem::size_of::<&str>() as u64;
}
}
}

macro_rules! sort_expensive {
($f:ident, $name:ident, $gen:expr, $len:expr) => {
#[bench]
fn $name(b: &mut Bencher) {
let v = $gen($len);
b.iter(|| {
let mut v = $gen($len);
let mut v = v.clone();
let mut count = 0;
v.$f(|a: &u64, b: &u64| {
count += 1;
Expand All @@ -263,38 +279,38 @@ macro_rules! sort_expensive {
});
black_box(count);
});
b.bytes = $len as u64 * mem::size_of::<u64>() as u64;
b.bytes = $len * mem::size_of_val(&$gen(1)[0]) as u64;
}
}
}

sort!(sort, sort_small_ascending, gen_ascending, 10);
sort!(sort, sort_small_descending, gen_descending, 10);
sort!(sort, sort_small_random, gen_random, 10);
sort!(sort, sort_small_big_random, gen_big_random, 10);
sort!(sort, sort_small_big, gen_big_random, 10);
sort!(sort, sort_medium_random, gen_random, 100);
sort!(sort, sort_large_ascending, gen_ascending, 10000);
sort!(sort, sort_large_descending, gen_descending, 10000);
sort!(sort, sort_large_mostly_ascending, gen_mostly_ascending, 10000);
sort!(sort, sort_large_mostly_descending, gen_mostly_descending, 10000);
sort!(sort, sort_large_random, gen_random, 10000);
sort!(sort, sort_large_big_random, gen_big_random, 10000);
sort!(sort, sort_large_strings, gen_strings, 10000);
sort_expensive!(sort_by, sort_large_random_expensive, gen_random, 10000);
sort!(sort, sort_large_big, gen_big_random, 10000);
sort_strings!(sort, sort_large_strings, gen_strings, 10000);
sort_expensive!(sort_by, sort_large_expensive, gen_random, 10000);

sort!(sort_unstable, sort_unstable_small_ascending, gen_ascending, 10);
sort!(sort_unstable, sort_unstable_small_descending, gen_descending, 10);
sort!(sort_unstable, sort_unstable_small_random, gen_random, 10);
sort!(sort_unstable, sort_unstable_small_big_random, gen_big_random, 10);
sort!(sort_unstable, sort_unstable_small_big, gen_big_random, 10);
sort!(sort_unstable, sort_unstable_medium_random, gen_random, 100);
sort!(sort_unstable, sort_unstable_large_ascending, gen_ascending, 10000);
sort!(sort_unstable, sort_unstable_large_descending, gen_descending, 10000);
sort!(sort_unstable, sort_unstable_large_mostly_ascending, gen_mostly_ascending, 10000);
sort!(sort_unstable, sort_unstable_large_mostly_descending, gen_mostly_descending, 10000);
sort!(sort_unstable, sort_unstable_large_random, gen_random, 10000);
sort!(sort_unstable, sort_unstable_large_big_random, gen_big_random, 10000);
sort!(sort_unstable, sort_unstable_large_strings, gen_strings, 10000);
sort_expensive!(sort_unstable_by, sort_unstable_large_random_expensive, gen_random, 10000);
sort!(sort_unstable, sort_unstable_large_big, gen_big_random, 10000);
sort_strings!(sort_unstable, sort_unstable_large_strings, gen_strings, 10000);
sort_expensive!(sort_unstable_by, sort_unstable_large_expensive, gen_random, 10000);

macro_rules! reverse {
($name:ident, $ty:ty, $f:expr) => {
Expand Down
4 changes: 2 additions & 2 deletions src/liballoc/slice.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1794,7 +1794,7 @@ unsafe fn merge<T, F>(v: &mut [T], mid: usize, buf: *mut T, is_less: &mut F)

impl<T> Drop for MergeHole<T> {
fn drop(&mut self) {
// `T` is not a zero-sized type, so it's okay to divide by it's size.
// `T` is not a zero-sized type, so it's okay to divide by its size.
let len = (self.end as usize - self.start as usize) / mem::size_of::<T>();
unsafe { ptr::copy_nonoverlapping(self.start, self.dest, len); }
}
Expand Down Expand Up @@ -1908,7 +1908,7 @@ fn merge_sort<T, F>(v: &mut [T], mut is_less: F)
// if `Some(r)` is returned, that means `runs[r]` and `runs[r + 1]` must be merged next. If the
// algorithm should continue building a new run instead, `None` is returned.
//
// TimSort is infamous for it's buggy implementations, as described here:
// TimSort is infamous for its buggy implementations, as described here:
// http://envisage-project.eu/timsort-specification-and-verification/
//
// The gist of the story is: we must enforce the invariants on the top four runs on the stack.
Expand Down
50 changes: 38 additions & 12 deletions src/liballoc/tests/slice.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -396,18 +396,44 @@ fn test_sort() {
let mut rng = thread_rng();

for len in (2..25).chain(500..510) {
for _ in 0..100 {
let mut v: Vec<_> = rng.gen_iter::<i32>().take(len).collect();
let mut v1 = v.clone();

v.sort();
assert!(v.windows(2).all(|w| w[0] <= w[1]));

v1.sort_by(|a, b| a.cmp(b));
assert!(v1.windows(2).all(|w| w[0] <= w[1]));

v1.sort_by(|a, b| b.cmp(a));
assert!(v1.windows(2).all(|w| w[0] >= w[1]));
for &modulus in &[5, 10, 100, 1000] {
for _ in 0..10 {
let orig: Vec<_> = rng.gen_iter::<i32>()
.map(|x| x % modulus)
.take(len)
.collect();

// Sort in default order.
let mut v = orig.clone();
v.sort();
assert!(v.windows(2).all(|w| w[0] <= w[1]));

// Sort in ascending order.
let mut v = orig.clone();
v.sort_by(|a, b| a.cmp(b));
assert!(v.windows(2).all(|w| w[0] <= w[1]));

// Sort in descending order.
let mut v = orig.clone();
v.sort_by(|a, b| b.cmp(a));
assert!(v.windows(2).all(|w| w[0] >= w[1]));

// Sort with many pre-sorted runs.
let mut v = orig.clone();
v.sort();
v.reverse();
for _ in 0..5 {
let a = rng.gen::<usize>() % len;
let b = rng.gen::<usize>() % len;
if a < b {
v[a..b].reverse();
} else {
v.swap(a, b);
}
}
v.sort();
assert!(v.windows(2).all(|w| w[0] <= w[1]));
}
}
}

Expand Down
Loading