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extern crate crossbeam_utils;
use std::sync::atomic::AtomicUsize;
use std::sync::atomic::Ordering::SeqCst;
use crossbeam_utils::atomic::AtomicCell;
#[test]
fn is_lock_free() {
struct UsizeWrap(usize);
struct U8Wrap(bool);
struct I16Wrap(i16);
assert_eq!(AtomicCell::<usize>::is_lock_free(), true);
assert_eq!(AtomicCell::<isize>::is_lock_free(), true);
assert_eq!(AtomicCell::<UsizeWrap>::is_lock_free(), true);
assert_eq!(AtomicCell::<u8>::is_lock_free(), cfg!(has_atomic_u8));
assert_eq!(AtomicCell::<bool>::is_lock_free(), cfg!(has_atomic_u8));
assert_eq!(AtomicCell::<U8Wrap>::is_lock_free(), cfg!(has_atomic_u8));
assert_eq!(AtomicCell::<I16Wrap>::is_lock_free(), cfg!(has_atomic_u16));
assert_eq!(AtomicCell::<u128>::is_lock_free(), cfg!(has_atomic_u128));
}
#[test]
fn drops_unit() {
static CNT: AtomicUsize = AtomicUsize::new(0);
CNT.store(0, SeqCst);
#[derive(Debug, PartialEq, Eq)]
struct Foo();
impl Foo {
fn new() -> Foo {
CNT.fetch_add(1, SeqCst);
Foo()
}
}
impl Drop for Foo {
fn drop(&mut self) {
CNT.fetch_sub(1, SeqCst);
}
}
impl Default for Foo {
fn default() -> Foo {
Foo::new()
}
}
let a = AtomicCell::new(Foo::new());
assert_eq!(a.swap(Foo::new()), Foo::new());
assert_eq!(CNT.load(SeqCst), 1);
a.store(Foo::new());
assert_eq!(CNT.load(SeqCst), 1);
assert_eq!(a.swap(Foo::default()), Foo::new());
assert_eq!(CNT.load(SeqCst), 1);
drop(a);
assert_eq!(CNT.load(SeqCst), 0);
}
#[test]
fn drops_u8() {
static CNT: AtomicUsize = AtomicUsize::new(0);
CNT.store(0, SeqCst);
#[derive(Debug, PartialEq, Eq)]
struct Foo(u8);
impl Foo {
fn new(val: u8) -> Foo {
CNT.fetch_add(1, SeqCst);
Foo(val)
}
}
impl Drop for Foo {
fn drop(&mut self) {
CNT.fetch_sub(1, SeqCst);
}
}
impl Default for Foo {
fn default() -> Foo {
Foo::new(0)
}
}
let a = AtomicCell::new(Foo::new(5));
assert_eq!(a.swap(Foo::new(6)), Foo::new(5));
assert_eq!(a.swap(Foo::new(1)), Foo::new(6));
assert_eq!(CNT.load(SeqCst), 1);
a.store(Foo::new(2));
assert_eq!(CNT.load(SeqCst), 1);
assert_eq!(a.swap(Foo::default()), Foo::new(2));
assert_eq!(CNT.load(SeqCst), 1);
assert_eq!(a.swap(Foo::default()), Foo::new(0));
assert_eq!(CNT.load(SeqCst), 1);
drop(a);
assert_eq!(CNT.load(SeqCst), 0);
}
#[test]
fn drops_usize() {
static CNT: AtomicUsize = AtomicUsize::new(0);
CNT.store(0, SeqCst);
#[derive(Debug, PartialEq, Eq)]
struct Foo(usize);
impl Foo {
fn new(val: usize) -> Foo {
CNT.fetch_add(1, SeqCst);
Foo(val)
}
}
impl Drop for Foo {
fn drop(&mut self) {
CNT.fetch_sub(1, SeqCst);
}
}
impl Default for Foo {
fn default() -> Foo {
Foo::new(0)
}
}
let a = AtomicCell::new(Foo::new(5));
assert_eq!(a.swap(Foo::new(6)), Foo::new(5));
assert_eq!(a.swap(Foo::new(1)), Foo::new(6));
assert_eq!(CNT.load(SeqCst), 1);
a.store(Foo::new(2));
assert_eq!(CNT.load(SeqCst), 1);
assert_eq!(a.swap(Foo::default()), Foo::new(2));
assert_eq!(CNT.load(SeqCst), 1);
assert_eq!(a.swap(Foo::default()), Foo::new(0));
assert_eq!(CNT.load(SeqCst), 1);
drop(a);
assert_eq!(CNT.load(SeqCst), 0);
}
#[test]
fn modular_u8() {
#[derive(Clone, Copy, Eq, Debug, Default)]
struct Foo(u8);
impl PartialEq for Foo {
fn eq(&self, other: &Foo) -> bool {
self.0 % 5 == other.0 % 5
}
}
let a = AtomicCell::new(Foo(1));
assert_eq!(a.load(), Foo(1));
assert_eq!(a.swap(Foo(2)), Foo(11));
assert_eq!(a.load(), Foo(52));
a.store(Foo(0));
assert_eq!(a.compare_exchange(Foo(0), Foo(5)), Ok(Foo(100)));
assert_eq!(a.load().0, 5);
assert_eq!(a.compare_exchange(Foo(10), Foo(15)), Ok(Foo(100)));
assert_eq!(a.load().0, 15);
}
#[test]
fn modular_usize() {
#[derive(Clone, Copy, Eq, Debug, Default)]
struct Foo(usize);
impl PartialEq for Foo {
fn eq(&self, other: &Foo) -> bool {
self.0 % 5 == other.0 % 5
}
}
let a = AtomicCell::new(Foo(1));
assert_eq!(a.load(), Foo(1));
assert_eq!(a.swap(Foo(2)), Foo(11));
assert_eq!(a.load(), Foo(52));
a.store(Foo(0));
assert_eq!(a.compare_exchange(Foo(0), Foo(5)), Ok(Foo(100)));
assert_eq!(a.load().0, 5);
assert_eq!(a.compare_exchange(Foo(10), Foo(15)), Ok(Foo(100)));
assert_eq!(a.load().0, 15);
}
#[test]
fn garbage_padding() {
#[derive(Copy, Clone, Eq, PartialEq)]
struct Object {
a: i64,
b: i32,
}
let cell = AtomicCell::new(Object { a: 0, b: 0 });
let _garbage = [0xfe, 0xfe, 0xfe, 0xfe, 0xfe]; // Needed
let next = Object { a: 0, b: 0 };
let prev = cell.load();
assert!(cell.compare_exchange(prev, next).is_ok());
println!();
}
#[cfg(has_min_const_fn)]
#[test]
fn const_atomic_cell_new() {
static CELL: AtomicCell<usize> = AtomicCell::new(0);
CELL.store(1);
assert_eq!(CELL.load(), 1);
}
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