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// Copyright 2016-2017 The Servo Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// option. This file may not be copied, modified, or distributed
// except according to those terms.
//! A reduced fork of Firefox's malloc_size_of crate, for bundling with WebRender.
extern crate app_units;
extern crate euclid;
use std::hash::{BuildHasher, Hash};
use std::mem::size_of;
use std::ops::Range;
use std::os::raw::c_void;
use std::path::PathBuf;
/// A C function that takes a pointer to a heap allocation and returns its size.
type VoidPtrToSizeFn = unsafe extern "C" fn(ptr: *const c_void) -> usize;
/// Operations used when measuring heap usage of data structures.
pub struct MallocSizeOfOps {
/// A function that returns the size of a heap allocation.
pub size_of_op: VoidPtrToSizeFn,
/// Like `size_of_op`, but can take an interior pointer. Optional because
/// not all allocators support this operation. If it's not provided, some
/// memory measurements will actually be computed estimates rather than
/// real and accurate measurements.
pub enclosing_size_of_op: Option<VoidPtrToSizeFn>,
}
impl MallocSizeOfOps {
pub fn new(
size_of: VoidPtrToSizeFn,
malloc_enclosing_size_of: Option<VoidPtrToSizeFn>,
) -> Self {
MallocSizeOfOps {
size_of_op: size_of,
enclosing_size_of_op: malloc_enclosing_size_of,
}
}
/// Check if an allocation is empty. This relies on knowledge of how Rust
/// handles empty allocations, which may change in the future.
fn is_empty<T: ?Sized>(ptr: *const T) -> bool {
// The correct condition is this:
// `ptr as usize <= ::std::mem::align_of::<T>()`
// But we can't call align_of() on a ?Sized T. So we approximate it
// with the following. 256 is large enough that it should always be
// larger than the required alignment, but small enough that it is
// always in the first page of memory and therefore not a legitimate
// address.
ptr as *const usize as usize <= 256
}
/// Call `size_of_op` on `ptr`, first checking that the allocation isn't
/// empty, because some types (such as `Vec`) utilize empty allocations.
pub unsafe fn malloc_size_of<T: ?Sized>(&self, ptr: *const T) -> usize {
if MallocSizeOfOps::is_empty(ptr) {
0
} else {
(self.size_of_op)(ptr as *const c_void)
}
}
/// Is an `enclosing_size_of_op` available?
pub fn has_malloc_enclosing_size_of(&self) -> bool {
self.enclosing_size_of_op.is_some()
}
/// Call `enclosing_size_of_op`, which must be available, on `ptr`, which
/// must not be empty.
pub unsafe fn malloc_enclosing_size_of<T>(&self, ptr: *const T) -> usize {
assert!(!MallocSizeOfOps::is_empty(ptr));
(self.enclosing_size_of_op.unwrap())(ptr as *const c_void)
}
}
/// Trait for measuring the "deep" heap usage of a data structure. This is the
/// most commonly-used of the traits.
pub trait MallocSizeOf {
/// Measure the heap usage of all descendant heap-allocated structures, but
/// not the space taken up by the value itself.
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize;
}
/// Trait for measuring the "shallow" heap usage of a container.
pub trait MallocShallowSizeOf {
/// Measure the heap usage of immediate heap-allocated descendant
/// structures, but not the space taken up by the value itself. Anything
/// beyond the immediate descendants must be measured separately, using
/// iteration.
fn shallow_size_of(&self, ops: &mut MallocSizeOfOps) -> usize;
}
impl MallocSizeOf for String {
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
unsafe { ops.malloc_size_of(self.as_ptr()) }
}
}
impl<T: ?Sized> MallocShallowSizeOf for Box<T> {
fn shallow_size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
unsafe { ops.malloc_size_of(&**self) }
}
}
impl<T: MallocSizeOf + ?Sized> MallocSizeOf for Box<T> {
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
self.shallow_size_of(ops) + (**self).size_of(ops)
}
}
impl MallocSizeOf for () {
fn size_of(&self, _ops: &mut MallocSizeOfOps) -> usize {
0
}
}
impl<T1, T2> MallocSizeOf for (T1, T2)
where
T1: MallocSizeOf,
T2: MallocSizeOf,
{
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
self.0.size_of(ops) + self.1.size_of(ops)
}
}
impl<T1, T2, T3> MallocSizeOf for (T1, T2, T3)
where
T1: MallocSizeOf,
T2: MallocSizeOf,
T3: MallocSizeOf,
{
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
self.0.size_of(ops) + self.1.size_of(ops) + self.2.size_of(ops)
}
}
impl<T1, T2, T3, T4> MallocSizeOf for (T1, T2, T3, T4)
where
T1: MallocSizeOf,
T2: MallocSizeOf,
T3: MallocSizeOf,
T4: MallocSizeOf,
{
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
self.0.size_of(ops) + self.1.size_of(ops) + self.2.size_of(ops) + self.3.size_of(ops)
}
}
impl<T: MallocSizeOf> MallocSizeOf for Option<T> {
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
if let Some(val) = self.as_ref() {
val.size_of(ops)
} else {
0
}
}
}
impl<T: MallocSizeOf, E: MallocSizeOf> MallocSizeOf for Result<T, E> {
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
match *self {
Ok(ref x) => x.size_of(ops),
Err(ref e) => e.size_of(ops),
}
}
}
impl<T: MallocSizeOf + Copy> MallocSizeOf for std::cell::Cell<T> {
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
self.get().size_of(ops)
}
}
impl<T: MallocSizeOf> MallocSizeOf for std::cell::RefCell<T> {
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
self.borrow().size_of(ops)
}
}
impl<'a, B: ?Sized + ToOwned> MallocSizeOf for std::borrow::Cow<'a, B>
where
B::Owned: MallocSizeOf,
{
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
match *self {
std::borrow::Cow::Borrowed(_) => 0,
std::borrow::Cow::Owned(ref b) => b.size_of(ops),
}
}
}
impl<T: MallocSizeOf> MallocSizeOf for [T] {
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
let mut n = 0;
for elem in self.iter() {
n += elem.size_of(ops);
}
n
}
}
impl<T> MallocShallowSizeOf for Vec<T> {
fn shallow_size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
unsafe { ops.malloc_size_of(self.as_ptr()) }
}
}
impl<T: MallocSizeOf> MallocSizeOf for Vec<T> {
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
let mut n = self.shallow_size_of(ops);
for elem in self.iter() {
n += elem.size_of(ops);
}
n
}
}
macro_rules! malloc_size_of_hash_set {
($ty:ty) => {
impl<T, S> MallocShallowSizeOf for $ty
where
T: Eq + Hash,
S: BuildHasher,
{
fn shallow_size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
if ops.has_malloc_enclosing_size_of() {
// The first value from the iterator gives us an interior pointer.
// `ops.malloc_enclosing_size_of()` then gives us the storage size.
// This assumes that the `HashSet`'s contents (values and hashes)
// are all stored in a single contiguous heap allocation.
self.iter()
.next()
.map_or(0, |t| unsafe { ops.malloc_enclosing_size_of(t) })
} else {
// An estimate.
self.capacity() * (size_of::<T>() + size_of::<usize>())
}
}
}
impl<T, S> MallocSizeOf for $ty
where
T: Eq + Hash + MallocSizeOf,
S: BuildHasher,
{
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
let mut n = self.shallow_size_of(ops);
for t in self.iter() {
n += t.size_of(ops);
}
n
}
}
};
}
malloc_size_of_hash_set!(std::collections::HashSet<T, S>);
macro_rules! malloc_size_of_hash_map {
($ty:ty) => {
impl<K, V, S> MallocShallowSizeOf for $ty
where
K: Eq + Hash,
S: BuildHasher,
{
fn shallow_size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
// See the implementation for std::collections::HashSet for details.
if ops.has_malloc_enclosing_size_of() {
self.values()
.next()
.map_or(0, |v| unsafe { ops.malloc_enclosing_size_of(v) })
} else {
self.capacity() * (size_of::<V>() + size_of::<K>() + size_of::<usize>())
}
}
}
impl<K, V, S> MallocSizeOf for $ty
where
K: Eq + Hash + MallocSizeOf,
V: MallocSizeOf,
S: BuildHasher,
{
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
let mut n = self.shallow_size_of(ops);
for (k, v) in self.iter() {
n += k.size_of(ops);
n += v.size_of(ops);
}
n
}
}
};
}
malloc_size_of_hash_map!(std::collections::HashMap<K, V, S>);
// PhantomData is always 0.
impl<T> MallocSizeOf for std::marker::PhantomData<T> {
fn size_of(&self, _ops: &mut MallocSizeOfOps) -> usize {
0
}
}
impl MallocSizeOf for PathBuf {
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
match self.to_str() {
Some(s) => unsafe { ops.malloc_size_of(s.as_ptr()) },
None => self.as_os_str().len(),
}
}
}
impl<T: MallocSizeOf, Unit> MallocSizeOf for euclid::Length<T, Unit> {
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
self.0.size_of(ops)
}
}
impl<T: MallocSizeOf, Src, Dst> MallocSizeOf for euclid::Scale<T, Src, Dst> {
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
self.0.size_of(ops)
}
}
impl<T: MallocSizeOf, U> MallocSizeOf for euclid::Point2D<T, U> {
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
self.x.size_of(ops) + self.y.size_of(ops)
}
}
impl<T: MallocSizeOf, U> MallocSizeOf for euclid::Rect<T, U> {
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
self.origin.size_of(ops) + self.size.size_of(ops)
}
}
impl<T: MallocSizeOf, U> MallocSizeOf for euclid::Box2D<T, U> {
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
self.min.size_of(ops) + self.max.size_of(ops)
}
}
impl<T: MallocSizeOf, U> MallocSizeOf for euclid::SideOffsets2D<T, U> {
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
self.top.size_of(ops) +
self.right.size_of(ops) +
self.bottom.size_of(ops) +
self.left.size_of(ops)
}
}
impl<T: MallocSizeOf, U> MallocSizeOf for euclid::Size2D<T, U> {
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
self.width.size_of(ops) + self.height.size_of(ops)
}
}
impl<T: MallocSizeOf, Src, Dst> MallocSizeOf for euclid::Transform2D<T, Src, Dst> {
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
self.m11.size_of(ops) +
self.m12.size_of(ops) +
self.m21.size_of(ops) +
self.m22.size_of(ops) +
self.m31.size_of(ops) +
self.m32.size_of(ops)
}
}
impl<T: MallocSizeOf, Src, Dst> MallocSizeOf for euclid::Transform3D<T, Src, Dst> {
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
self.m11.size_of(ops) +
self.m12.size_of(ops) +
self.m13.size_of(ops) +
self.m14.size_of(ops) +
self.m21.size_of(ops) +
self.m22.size_of(ops) +
self.m23.size_of(ops) +
self.m24.size_of(ops) +
self.m31.size_of(ops) +
self.m32.size_of(ops) +
self.m33.size_of(ops) +
self.m34.size_of(ops) +
self.m41.size_of(ops) +
self.m42.size_of(ops) +
self.m43.size_of(ops) +
self.m44.size_of(ops)
}
}
impl<T: MallocSizeOf, U> MallocSizeOf for euclid::Vector2D<T, U> {
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
self.x.size_of(ops) + self.y.size_of(ops)
}
}
/// For use on types where size_of() returns 0.
#[macro_export]
macro_rules! malloc_size_of_is_0(
($($ty:ty),+) => (
$(
impl $crate::MallocSizeOf for $ty {
#[inline(always)]
fn size_of(&self, _: &mut $crate::MallocSizeOfOps) -> usize {
0
}
}
)+
);
($($ty:ident<$($gen:ident),+>),+) => (
$(
impl<$($gen: $crate::MallocSizeOf),+> $crate::MallocSizeOf for $ty<$($gen),+> {
#[inline(always)]
fn size_of(&self, _: &mut $crate::MallocSizeOfOps) -> usize {
0
}
}
)+
);
);
malloc_size_of_is_0!(bool, char, str);
malloc_size_of_is_0!(u8, u16, u32, u64, u128, usize);
malloc_size_of_is_0!(i8, i16, i32, i64, i128, isize);
malloc_size_of_is_0!(f32, f64);
malloc_size_of_is_0!(std::sync::atomic::AtomicBool);
malloc_size_of_is_0!(std::sync::atomic::AtomicIsize);
malloc_size_of_is_0!(std::sync::atomic::AtomicUsize);
malloc_size_of_is_0!(std::num::NonZeroUsize);
malloc_size_of_is_0!(std::num::NonZeroU32);
malloc_size_of_is_0!(std::time::Duration);
malloc_size_of_is_0!(std::time::Instant);
malloc_size_of_is_0!(std::time::SystemTime);
malloc_size_of_is_0!(Range<u8>, Range<u16>, Range<u32>, Range<u64>, Range<usize>);
malloc_size_of_is_0!(Range<i8>, Range<i16>, Range<i32>, Range<i64>, Range<isize>);
malloc_size_of_is_0!(Range<f32>, Range<f64>);
malloc_size_of_is_0!(app_units::Au);