1 files changed, 225 insertions, 0 deletions
diff --git a/third_party/rust/crossbeam-utils-0.6.6/tests/atomic_cell.rs b/third_party/rust/crossbeam-utils-0.6.6/tests/atomic_cell.rs
new file mode 100644
index 0000000000..9406192333
--- /dev/null
+++ b/third_party/rust/crossbeam-utils-0.6.6/tests/atomic_cell.rs
@@ -0,0 +1,225 @@
+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);
+
+    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!(feature = "nightly"));
+    assert_eq!(
+        AtomicCell::<bool>::is_lock_free(),
+        cfg!(feature = "nightly")
+    );
+    assert_eq!(
+        AtomicCell::<U8Wrap>::is_lock_free(),
+        cfg!(feature = "nightly")
+    );
+}
+
+#[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!();
+}