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-rw-r--r--vendor/crossbeam-epoch/tests/loom.rs157
1 files changed, 0 insertions, 157 deletions
diff --git a/vendor/crossbeam-epoch/tests/loom.rs b/vendor/crossbeam-epoch/tests/loom.rs
deleted file mode 100644
index 4e56acd..0000000
--- a/vendor/crossbeam-epoch/tests/loom.rs
+++ /dev/null
@@ -1,157 +0,0 @@
-#![cfg(crossbeam_loom)]
-
-use crossbeam_epoch as epoch;
-use loom_crate as loom;
-
-use epoch::*;
-use epoch::{Atomic, Owned};
-use loom::sync::atomic::Ordering::{self, Acquire, Relaxed, Release};
-use loom::sync::Arc;
-use loom::thread::spawn;
-use std::mem::ManuallyDrop;
-use std::ptr;
-
-#[test]
-fn it_works() {
- loom::model(|| {
- let collector = Collector::new();
- let item: Atomic<String> = Atomic::from(Owned::new(String::from("boom")));
- let item2 = item.clone();
- let collector2 = collector.clone();
- let guard = collector.register().pin();
-
- let jh = loom::thread::spawn(move || {
- let guard = collector2.register().pin();
- guard.defer(move || {
- // this isn't really safe, since other threads may still have pointers to the
- // value, but in this limited test scenario it's okay, since we know the test won't
- // access item after all the pins are released.
- let mut item = unsafe { item2.into_owned() };
- // mutate it as a second measure to make sure the assert_eq below would fail
- item.retain(|c| c == 'o');
- drop(item);
- });
- });
-
- let item = item.load(Ordering::SeqCst, &guard);
- // we pinned strictly before the call to defer_destroy,
- // so item cannot have been dropped yet
- assert_eq!(*unsafe { item.deref() }, "boom");
- drop(guard);
-
- jh.join().unwrap();
-
- drop(collector);
- })
-}
-
-#[test]
-fn treiber_stack() {
- /// Treiber's lock-free stack.
- ///
- /// Usable with any number of producers and consumers.
- #[derive(Debug)]
- pub struct TreiberStack<T> {
- head: Atomic<Node<T>>,
- }
-
- #[derive(Debug)]
- struct Node<T> {
- data: ManuallyDrop<T>,
- next: Atomic<Node<T>>,
- }
-
- impl<T> TreiberStack<T> {
- /// Creates a new, empty stack.
- pub fn new() -> TreiberStack<T> {
- TreiberStack {
- head: Atomic::null(),
- }
- }
-
- /// Pushes a value on top of the stack.
- pub fn push(&self, t: T) {
- let mut n = Owned::new(Node {
- data: ManuallyDrop::new(t),
- next: Atomic::null(),
- });
-
- let guard = epoch::pin();
-
- loop {
- let head = self.head.load(Relaxed, &guard);
- n.next.store(head, Relaxed);
-
- match self
- .head
- .compare_exchange(head, n, Release, Relaxed, &guard)
- {
- Ok(_) => break,
- Err(e) => n = e.new,
- }
- }
- }
-
- /// Attempts to pop the top element from the stack.
- ///
- /// Returns `None` if the stack is empty.
- pub fn pop(&self) -> Option<T> {
- let guard = epoch::pin();
- loop {
- let head = self.head.load(Acquire, &guard);
-
- match unsafe { head.as_ref() } {
- Some(h) => {
- let next = h.next.load(Relaxed, &guard);
-
- if self
- .head
- .compare_exchange(head, next, Relaxed, Relaxed, &guard)
- .is_ok()
- {
- unsafe {
- guard.defer_destroy(head);
- return Some(ManuallyDrop::into_inner(ptr::read(&(*h).data)));
- }
- }
- }
- None => return None,
- }
- }
- }
-
- /// Returns `true` if the stack is empty.
- pub fn is_empty(&self) -> bool {
- let guard = epoch::pin();
- self.head.load(Acquire, &guard).is_null()
- }
- }
-
- impl<T> Drop for TreiberStack<T> {
- fn drop(&mut self) {
- while self.pop().is_some() {}
- }
- }
-
- loom::model(|| {
- let stack1 = Arc::new(TreiberStack::new());
- let stack2 = Arc::clone(&stack1);
-
- // use 5 since it's greater than the 4 used for the sanitize feature
- let jh = spawn(move || {
- for i in 0..5 {
- stack2.push(i);
- assert!(stack2.pop().is_some());
- }
- });
-
- for i in 0..5 {
- stack1.push(i);
- assert!(stack1.pop().is_some());
- }
-
- jh.join().unwrap();
- assert!(stack1.pop().is_none());
- assert!(stack1.is_empty());
- });
-}