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|
extern crate test;
use super::TypedArena;
use std::cell::Cell;
use test::Bencher;
#[allow(dead_code)]
#[derive(Debug, Eq, PartialEq)]
struct Point {
x: i32,
y: i32,
z: i32,
}
impl<T> TypedArena<T> {
/// Clears the arena. Deallocates all but the longest chunk which may be reused.
fn clear(&mut self) {
unsafe {
// Clear the last chunk, which is partially filled.
let mut chunks_borrow = self.chunks.borrow_mut();
if let Some(mut last_chunk) = chunks_borrow.last_mut() {
self.clear_last_chunk(&mut last_chunk);
let len = chunks_borrow.len();
// If `T` is ZST, code below has no effect.
for mut chunk in chunks_borrow.drain(..len - 1) {
chunk.destroy(chunk.entries);
}
}
}
}
}
#[test]
pub fn test_unused() {
let arena: TypedArena<Point> = TypedArena::default();
assert!(arena.chunks.borrow().is_empty());
}
#[test]
fn test_arena_alloc_nested() {
struct Inner {
value: u8,
}
struct Outer<'a> {
inner: &'a Inner,
}
enum EI<'e> {
I(Inner),
O(Outer<'e>),
}
struct Wrap<'a>(TypedArena<EI<'a>>);
impl<'a> Wrap<'a> {
fn alloc_inner<F: Fn() -> Inner>(&self, f: F) -> &Inner {
let r: &EI<'_> = self.0.alloc(EI::I(f()));
if let &EI::I(ref i) = r {
i
} else {
panic!("mismatch");
}
}
fn alloc_outer<F: Fn() -> Outer<'a>>(&self, f: F) -> &Outer<'_> {
let r: &EI<'_> = self.0.alloc(EI::O(f()));
if let &EI::O(ref o) = r {
o
} else {
panic!("mismatch");
}
}
}
let arena = Wrap(TypedArena::default());
let result = arena.alloc_outer(|| Outer { inner: arena.alloc_inner(|| Inner { value: 10 }) });
assert_eq!(result.inner.value, 10);
}
#[test]
pub fn test_copy() {
let arena = TypedArena::default();
#[cfg(not(miri))]
const N: usize = 100000;
#[cfg(miri)]
const N: usize = 1000;
for _ in 0..N {
arena.alloc(Point { x: 1, y: 2, z: 3 });
}
}
#[bench]
pub fn bench_copy(b: &mut Bencher) {
let arena = TypedArena::default();
b.iter(|| arena.alloc(Point { x: 1, y: 2, z: 3 }))
}
#[bench]
pub fn bench_copy_nonarena(b: &mut Bencher) {
b.iter(|| {
let _: Box<_> = Box::new(Point { x: 1, y: 2, z: 3 });
})
}
#[allow(dead_code)]
struct Noncopy {
string: String,
array: Vec<i32>,
}
#[test]
pub fn test_noncopy() {
let arena = TypedArena::default();
#[cfg(not(miri))]
const N: usize = 100000;
#[cfg(miri)]
const N: usize = 1000;
for _ in 0..N {
arena.alloc(Noncopy { string: "hello world".to_string(), array: vec![1, 2, 3, 4, 5] });
}
}
#[test]
pub fn test_typed_arena_zero_sized() {
let arena = TypedArena::default();
#[cfg(not(miri))]
const N: usize = 100000;
#[cfg(miri)]
const N: usize = 1000;
for _ in 0..N {
arena.alloc(());
}
}
#[test]
pub fn test_typed_arena_clear() {
let mut arena = TypedArena::default();
for _ in 0..10 {
arena.clear();
#[cfg(not(miri))]
const N: usize = 10000;
#[cfg(miri)]
const N: usize = 100;
for _ in 0..N {
arena.alloc(Point { x: 1, y: 2, z: 3 });
}
}
}
#[bench]
pub fn bench_typed_arena_clear(b: &mut Bencher) {
let mut arena = TypedArena::default();
b.iter(|| {
arena.alloc(Point { x: 1, y: 2, z: 3 });
arena.clear();
})
}
#[bench]
pub fn bench_typed_arena_clear_100(b: &mut Bencher) {
let mut arena = TypedArena::default();
b.iter(|| {
for _ in 0..100 {
arena.alloc(Point { x: 1, y: 2, z: 3 });
}
arena.clear();
})
}
// Drop tests
struct DropCounter<'a> {
count: &'a Cell<u32>,
}
impl Drop for DropCounter<'_> {
fn drop(&mut self) {
self.count.set(self.count.get() + 1);
}
}
#[test]
fn test_typed_arena_drop_count() {
let counter = Cell::new(0);
{
let arena: TypedArena<DropCounter<'_>> = TypedArena::default();
for _ in 0..100 {
// Allocate something with drop glue to make sure it doesn't leak.
arena.alloc(DropCounter { count: &counter });
}
};
assert_eq!(counter.get(), 100);
}
#[test]
fn test_typed_arena_drop_on_clear() {
let counter = Cell::new(0);
let mut arena: TypedArena<DropCounter<'_>> = TypedArena::default();
for i in 0..10 {
for _ in 0..100 {
// Allocate something with drop glue to make sure it doesn't leak.
arena.alloc(DropCounter { count: &counter });
}
arena.clear();
assert_eq!(counter.get(), i * 100 + 100);
}
}
thread_local! {
static DROP_COUNTER: Cell<u32> = Cell::new(0)
}
struct SmallDroppable;
impl Drop for SmallDroppable {
fn drop(&mut self) {
DROP_COUNTER.with(|c| c.set(c.get() + 1));
}
}
#[test]
fn test_typed_arena_drop_small_count() {
DROP_COUNTER.with(|c| c.set(0));
{
let arena: TypedArena<SmallDroppable> = TypedArena::default();
for _ in 0..100 {
// Allocate something with drop glue to make sure it doesn't leak.
arena.alloc(SmallDroppable);
}
// dropping
};
assert_eq!(DROP_COUNTER.with(|c| c.get()), 100);
}
#[bench]
pub fn bench_noncopy(b: &mut Bencher) {
let arena = TypedArena::default();
b.iter(|| {
arena.alloc(Noncopy { string: "hello world".to_string(), array: vec![1, 2, 3, 4, 5] })
})
}
#[bench]
pub fn bench_noncopy_nonarena(b: &mut Bencher) {
b.iter(|| {
let _: Box<_> =
Box::new(Noncopy { string: "hello world".to_string(), array: vec![1, 2, 3, 4, 5] });
})
}
|
