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//! Benchmark sqrt and cbrt
#![feature(test)]
extern crate num_integer;
extern crate num_traits;
extern crate test;
use num_integer::Integer;
use num_traits::{AsPrimitive, PrimInt, WrappingAdd, WrappingMul};
use std::cmp::{max, min};
use std::fmt::Debug;
use test::{black_box, Bencher};
// --- Utilities for RNG ----------------------------------------------------
trait BenchInteger: Integer + PrimInt + WrappingAdd + WrappingMul + 'static {}
impl<T> BenchInteger for T where T: Integer + PrimInt + WrappingAdd + WrappingMul + 'static {}
// Simple PRNG so we don't have to worry about rand compatibility
fn lcg<T>(x: T) -> T
where
u32: AsPrimitive<T>,
T: BenchInteger,
{
// LCG parameters from Numerical Recipes
// (but we're applying it to arbitrary sizes)
const LCG_A: u32 = 1664525;
const LCG_C: u32 = 1013904223;
x.wrapping_mul(&LCG_A.as_()).wrapping_add(&LCG_C.as_())
}
// --- Alt. Implementations -------------------------------------------------
trait NaiveAverage {
fn naive_average_ceil(&self, other: &Self) -> Self;
fn naive_average_floor(&self, other: &Self) -> Self;
}
trait UncheckedAverage {
fn unchecked_average_ceil(&self, other: &Self) -> Self;
fn unchecked_average_floor(&self, other: &Self) -> Self;
}
trait ModuloAverage {
fn modulo_average_ceil(&self, other: &Self) -> Self;
fn modulo_average_floor(&self, other: &Self) -> Self;
}
macro_rules! naive_average {
($T:ident) => {
impl super::NaiveAverage for $T {
fn naive_average_floor(&self, other: &$T) -> $T {
match self.checked_add(*other) {
Some(z) => Integer::div_floor(&z, &2),
None => {
if self > other {
let diff = self - other;
other + Integer::div_floor(&diff, &2)
} else {
let diff = other - self;
self + Integer::div_floor(&diff, &2)
}
}
}
}
fn naive_average_ceil(&self, other: &$T) -> $T {
match self.checked_add(*other) {
Some(z) => Integer::div_ceil(&z, &2),
None => {
if self > other {
let diff = self - other;
self - Integer::div_floor(&diff, &2)
} else {
let diff = other - self;
other - Integer::div_floor(&diff, &2)
}
}
}
}
}
};
}
macro_rules! unchecked_average {
($T:ident) => {
impl super::UncheckedAverage for $T {
fn unchecked_average_floor(&self, other: &$T) -> $T {
self.wrapping_add(*other) / 2
}
fn unchecked_average_ceil(&self, other: &$T) -> $T {
(self.wrapping_add(*other) / 2).wrapping_add(1)
}
}
};
}
macro_rules! modulo_average {
($T:ident) => {
impl super::ModuloAverage for $T {
fn modulo_average_ceil(&self, other: &$T) -> $T {
let (q1, r1) = self.div_mod_floor(&2);
let (q2, r2) = other.div_mod_floor(&2);
q1 + q2 + (r1 | r2)
}
fn modulo_average_floor(&self, other: &$T) -> $T {
let (q1, r1) = self.div_mod_floor(&2);
let (q2, r2) = other.div_mod_floor(&2);
q1 + q2 + (r1 * r2)
}
}
};
}
// --- Bench functions ------------------------------------------------------
fn bench_unchecked<T, F>(b: &mut Bencher, v: &[(T, T)], f: F)
where
T: Integer + Debug + Copy,
F: Fn(&T, &T) -> T,
{
b.iter(|| {
for (x, y) in v {
black_box(f(x, y));
}
});
}
fn bench_ceil<T, F>(b: &mut Bencher, v: &[(T, T)], f: F)
where
T: Integer + Debug + Copy,
F: Fn(&T, &T) -> T,
{
for &(i, j) in v {
let rt = f(&i, &j);
let (a, b) = (min(i, j), max(i, j));
// if both number are the same sign, check rt is in the middle
if (a < T::zero()) == (b < T::zero()) {
if (b - a).is_even() {
assert_eq!(rt - a, b - rt);
} else {
assert_eq!(rt - a, b - rt + T::one());
}
// if both number have a different sign,
} else {
if (a + b).is_even() {
assert_eq!(rt, (a + b) / (T::one() + T::one()))
} else {
assert_eq!(rt, (a + b + T::one()) / (T::one() + T::one()))
}
}
}
bench_unchecked(b, v, f);
}
fn bench_floor<T, F>(b: &mut Bencher, v: &[(T, T)], f: F)
where
T: Integer + Debug + Copy,
F: Fn(&T, &T) -> T,
{
for &(i, j) in v {
let rt = f(&i, &j);
let (a, b) = (min(i, j), max(i, j));
// if both number are the same sign, check rt is in the middle
if (a < T::zero()) == (b < T::zero()) {
if (b - a).is_even() {
assert_eq!(rt - a, b - rt);
} else {
assert_eq!(rt - a + T::one(), b - rt);
}
// if both number have a different sign,
} else {
if (a + b).is_even() {
assert_eq!(rt, (a + b) / (T::one() + T::one()))
} else {
assert_eq!(rt, (a + b - T::one()) / (T::one() + T::one()))
}
}
}
bench_unchecked(b, v, f);
}
// --- Bench implementation -------------------------------------------------
macro_rules! bench_average {
($($T:ident),*) => {$(
mod $T {
use test::Bencher;
use num_integer::{Average, Integer};
use super::{UncheckedAverage, NaiveAverage, ModuloAverage};
use super::{bench_ceil, bench_floor, bench_unchecked};
naive_average!($T);
unchecked_average!($T);
modulo_average!($T);
const SIZE: $T = 30;
fn overflowing() -> Vec<($T, $T)> {
(($T::max_value()-SIZE)..$T::max_value())
.flat_map(|x| -> Vec<_> {
(($T::max_value()-100)..($T::max_value()-100+SIZE))
.map(|y| (x, y))
.collect()
})
.collect()
}
fn small() -> Vec<($T, $T)> {
(0..SIZE)
.flat_map(|x| -> Vec<_> {(0..SIZE).map(|y| (x, y)).collect()})
.collect()
}
fn rand() -> Vec<($T, $T)> {
small()
.into_iter()
.map(|(x, y)| (super::lcg(x), super::lcg(y)))
.collect()
}
mod ceil {
use super::*;
mod small {
use super::*;
#[bench]
fn optimized(b: &mut Bencher) {
let v = small();
bench_ceil(b, &v, |x: &$T, y: &$T| x.average_ceil(y));
}
#[bench]
fn naive(b: &mut Bencher) {
let v = small();
bench_ceil(b, &v, |x: &$T, y: &$T| x.naive_average_ceil(y));
}
#[bench]
fn unchecked(b: &mut Bencher) {
let v = small();
bench_unchecked(b, &v, |x: &$T, y: &$T| x.unchecked_average_ceil(y));
}
#[bench]
fn modulo(b: &mut Bencher) {
let v = small();
bench_ceil(b, &v, |x: &$T, y: &$T| x.modulo_average_ceil(y));
}
}
mod overflowing {
use super::*;
#[bench]
fn optimized(b: &mut Bencher) {
let v = overflowing();
bench_ceil(b, &v, |x: &$T, y: &$T| x.average_ceil(y));
}
#[bench]
fn naive(b: &mut Bencher) {
let v = overflowing();
bench_ceil(b, &v, |x: &$T, y: &$T| x.naive_average_ceil(y));
}
#[bench]
fn unchecked(b: &mut Bencher) {
let v = overflowing();
bench_unchecked(b, &v, |x: &$T, y: &$T| x.unchecked_average_ceil(y));
}
#[bench]
fn modulo(b: &mut Bencher) {
let v = overflowing();
bench_ceil(b, &v, |x: &$T, y: &$T| x.modulo_average_ceil(y));
}
}
mod rand {
use super::*;
#[bench]
fn optimized(b: &mut Bencher) {
let v = rand();
bench_ceil(b, &v, |x: &$T, y: &$T| x.average_ceil(y));
}
#[bench]
fn naive(b: &mut Bencher) {
let v = rand();
bench_ceil(b, &v, |x: &$T, y: &$T| x.naive_average_ceil(y));
}
#[bench]
fn unchecked(b: &mut Bencher) {
let v = rand();
bench_unchecked(b, &v, |x: &$T, y: &$T| x.unchecked_average_ceil(y));
}
#[bench]
fn modulo(b: &mut Bencher) {
let v = rand();
bench_ceil(b, &v, |x: &$T, y: &$T| x.modulo_average_ceil(y));
}
}
}
mod floor {
use super::*;
mod small {
use super::*;
#[bench]
fn optimized(b: &mut Bencher) {
let v = small();
bench_floor(b, &v, |x: &$T, y: &$T| x.average_floor(y));
}
#[bench]
fn naive(b: &mut Bencher) {
let v = small();
bench_floor(b, &v, |x: &$T, y: &$T| x.naive_average_floor(y));
}
#[bench]
fn unchecked(b: &mut Bencher) {
let v = small();
bench_unchecked(b, &v, |x: &$T, y: &$T| x.unchecked_average_floor(y));
}
#[bench]
fn modulo(b: &mut Bencher) {
let v = small();
bench_floor(b, &v, |x: &$T, y: &$T| x.modulo_average_floor(y));
}
}
mod overflowing {
use super::*;
#[bench]
fn optimized(b: &mut Bencher) {
let v = overflowing();
bench_floor(b, &v, |x: &$T, y: &$T| x.average_floor(y));
}
#[bench]
fn naive(b: &mut Bencher) {
let v = overflowing();
bench_floor(b, &v, |x: &$T, y: &$T| x.naive_average_floor(y));
}
#[bench]
fn unchecked(b: &mut Bencher) {
let v = overflowing();
bench_unchecked(b, &v, |x: &$T, y: &$T| x.unchecked_average_floor(y));
}
#[bench]
fn modulo(b: &mut Bencher) {
let v = overflowing();
bench_floor(b, &v, |x: &$T, y: &$T| x.modulo_average_floor(y));
}
}
mod rand {
use super::*;
#[bench]
fn optimized(b: &mut Bencher) {
let v = rand();
bench_floor(b, &v, |x: &$T, y: &$T| x.average_floor(y));
}
#[bench]
fn naive(b: &mut Bencher) {
let v = rand();
bench_floor(b, &v, |x: &$T, y: &$T| x.naive_average_floor(y));
}
#[bench]
fn unchecked(b: &mut Bencher) {
let v = rand();
bench_unchecked(b, &v, |x: &$T, y: &$T| x.unchecked_average_floor(y));
}
#[bench]
fn modulo(b: &mut Bencher) {
let v = rand();
bench_floor(b, &v, |x: &$T, y: &$T| x.modulo_average_floor(y));
}
}
}
}
)*}
}
bench_average!(i8, i16, i32, i64, i128, isize);
bench_average!(u8, u16, u32, u64, u128, usize);