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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 crate for measuring the heap usage of data structures in a way that
//! integrates with Firefox's memory reporting, particularly the use of
//! mozjemalloc and DMD. In particular, it has the following features.
//! - It isn't bound to a particular heap allocator.
//! - It provides traits for both "shallow" and "deep" measurement, which gives
//! flexibility in the cases where the traits can't be used.
//! - It allows for measuring blocks even when only an interior pointer can be
//! obtained for heap allocations, e.g. `HashSet` and `HashMap`. (This relies
//! on the heap allocator having suitable support, which mozjemalloc has.)
//! - It allows handling of types like `Rc` and `Arc` by providing traits that
//! are different to the ones for non-graph structures.
//!
//! Suggested uses are as follows.
//! - When possible, use the `MallocSizeOf` trait. (Deriving support is
//! provided by the `malloc_size_of_derive` crate.)
//! - If you need an additional synchronization argument, provide a function
//! that is like the standard trait method, but with the extra argument.
//! - If you need multiple measurements for a type, provide a function named
//! `add_size_of` that takes a mutable reference to a struct that contains
//! the multiple measurement fields.
//! - When deep measurement (via `MallocSizeOf`) cannot be implemented for a
//! type, shallow measurement (via `MallocShallowSizeOf`) in combination with
//! iteration can be a useful substitute.
//! - `Rc` and `Arc` are always tricky, which is why `MallocSizeOf` is not (and
//! should not be) implemented for them.
//! - If an `Rc` or `Arc` is known to be a "primary" reference and can always
//! be measured, it should be measured via the `MallocUnconditionalSizeOf`
//! trait.
//! - If an `Rc` or `Arc` should be measured only if it hasn't been seen
//! before, it should be measured via the `MallocConditionalSizeOf` trait.
//! - Using universal function call syntax is a good idea when measuring boxed
//! fields in structs, because it makes it clear that the Box is being
//! measured as well as the thing it points to. E.g.
//! `<Box<_> as MallocSizeOf>::size_of(field, ops)`.
//!
//! Note: WebRender has a reduced fork of this crate, so that we can avoid
//! publishing this crate on crates.io.
extern crate app_units;
extern crate cssparser;
extern crate euclid;
extern crate selectors;
extern crate servo_arc;
extern crate smallbitvec;
extern crate smallvec;
extern crate void;
use std::hash::{BuildHasher, Hash};
use std::mem::size_of;
use std::ops::Range;
use std::ops::{Deref, DerefMut};
use std::os::raw::c_void;
use void::Void;
/// 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;
/// A closure implementing a stateful predicate on pointers.
type VoidPtrToBoolFnMut = dyn FnMut(*const c_void) -> bool;
/// Operations used when measuring heap usage of data structures.
pub struct MallocSizeOfOps {
/// A function that returns the size of a heap allocation.
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.
enclosing_size_of_op: Option<VoidPtrToSizeFn>,
/// Check if a pointer has been seen before, and remember it for next time.
/// Useful when measuring `Rc`s and `Arc`s. Optional, because many places
/// don't need it.
have_seen_ptr_op: Option<Box<VoidPtrToBoolFnMut>>,
}
impl MallocSizeOfOps {
pub fn new(
size_of: VoidPtrToSizeFn,
malloc_enclosing_size_of: Option<VoidPtrToSizeFn>,
have_seen_ptr: Option<Box<VoidPtrToBoolFnMut>>,
) -> Self {
MallocSizeOfOps {
size_of_op: size_of,
enclosing_size_of_op: malloc_enclosing_size_of,
have_seen_ptr_op: have_seen_ptr,
}
}
/// 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.
return 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)
}
/// Call `have_seen_ptr_op` on `ptr`.
pub fn have_seen_ptr<T>(&mut self, ptr: *const T) -> bool {
let have_seen_ptr_op = self
.have_seen_ptr_op
.as_mut()
.expect("missing have_seen_ptr_op");
have_seen_ptr_op(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;
}
/// Like `MallocSizeOf`, but with a different name so it cannot be used
/// accidentally with derive(MallocSizeOf). For use with types like `Rc` and
/// `Arc` when appropriate (e.g. when measuring a "primary" reference).
pub trait MallocUnconditionalSizeOf {
/// Measure the heap usage of all heap-allocated descendant structures, but
/// not the space taken up by the value itself.
fn unconditional_size_of(&self, ops: &mut MallocSizeOfOps) -> usize;
}
/// `MallocUnconditionalSizeOf` combined with `MallocShallowSizeOf`.
pub trait MallocUnconditionalShallowSizeOf {
/// `unconditional_size_of` combined with `shallow_size_of`.
fn unconditional_shallow_size_of(&self, ops: &mut MallocSizeOfOps) -> usize;
}
/// Like `MallocSizeOf`, but only measures if the value hasn't already been
/// measured. For use with types like `Rc` and `Arc` when appropriate (e.g.
/// when there is no "primary" reference).
pub trait MallocConditionalSizeOf {
/// Measure the heap usage of all heap-allocated descendant structures, but
/// not the space taken up by the value itself, and only if that heap usage
/// hasn't already been measured.
fn conditional_size_of(&self, ops: &mut MallocSizeOfOps) -> usize;
}
/// `MallocConditionalSizeOf` combined with `MallocShallowSizeOf`.
pub trait MallocConditionalShallowSizeOf {
/// `conditional_size_of` combined with `shallow_size_of`.
fn conditional_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<'a, T: ?Sized> MallocSizeOf for &'a T {
fn size_of(&self, _ops: &mut MallocSizeOfOps) -> usize {
// Zero makes sense for a non-owning reference.
0
}
}
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
}
}
impl<T> MallocShallowSizeOf for std::collections::VecDeque<T> {
fn shallow_size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
if ops.has_malloc_enclosing_size_of() {
if let Some(front) = self.front() {
// The front element is an interior pointer.
unsafe { ops.malloc_enclosing_size_of(&*front) }
} else {
// This assumes that no memory is allocated when the VecDeque is empty.
0
}
} else {
// An estimate.
self.capacity() * size_of::<T>()
}
}
}
impl<T: MallocSizeOf> MallocSizeOf for std::collections::VecDeque<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
}
}
impl<A: smallvec::Array> MallocShallowSizeOf for smallvec::SmallVec<A> {
fn shallow_size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
if self.spilled() {
unsafe { ops.malloc_size_of(self.as_ptr()) }
} else {
0
}
}
}
impl<A> MallocSizeOf for smallvec::SmallVec<A>
where
A: smallvec::Array,
A::Item: MallocSizeOf,
{
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
}
}
impl<T> MallocShallowSizeOf for thin_vec::ThinVec<T> {
fn shallow_size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
if self.capacity() == 0 {
// If it's the singleton we might not be a heap pointer.
return 0;
}
assert_eq!(
std::mem::size_of::<Self>(),
std::mem::size_of::<*const ()>()
);
unsafe { ops.malloc_size_of(*(self as *const Self as *const *const ())) }
}
}
impl<T: MallocSizeOf> MallocSizeOf for thin_vec::ThinVec<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>);
impl<K, V> MallocShallowSizeOf for std::collections::BTreeMap<K, V>
where
K: Eq + Hash,
{
fn shallow_size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
if ops.has_malloc_enclosing_size_of() {
self.values()
.next()
.map_or(0, |v| unsafe { ops.malloc_enclosing_size_of(v) })
} else {
self.len() * (size_of::<V>() + size_of::<K>() + size_of::<usize>())
}
}
}
impl<K, V> MallocSizeOf for std::collections::BTreeMap<K, V>
where
K: Eq + Hash + MallocSizeOf,
V: MallocSizeOf,
{
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
}
}
// PhantomData is always 0.
impl<T> MallocSizeOf for std::marker::PhantomData<T> {
fn size_of(&self, _ops: &mut MallocSizeOfOps) -> usize {
0
}
}
// XXX: we don't want MallocSizeOf to be defined for Rc and Arc. If negative
// trait bounds are ever allowed, this code should be uncommented.
// (We do have a compile-fail test for this:
// rc_arc_must_not_derive_malloc_size_of.rs)
//impl<T> !MallocSizeOf for Arc<T> { }
//impl<T> !MallocShallowSizeOf for Arc<T> { }
impl<T> MallocUnconditionalShallowSizeOf for servo_arc::Arc<T> {
fn unconditional_shallow_size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
unsafe { ops.malloc_size_of(self.heap_ptr()) }
}
}
impl<T: MallocSizeOf> MallocUnconditionalSizeOf for servo_arc::Arc<T> {
fn unconditional_size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
self.unconditional_shallow_size_of(ops) + (**self).size_of(ops)
}
}
impl<T> MallocConditionalShallowSizeOf for servo_arc::Arc<T> {
fn conditional_shallow_size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
if ops.have_seen_ptr(self.heap_ptr()) {
0
} else {
self.unconditional_shallow_size_of(ops)
}
}
}
impl<T: MallocSizeOf> MallocConditionalSizeOf for servo_arc::Arc<T> {
fn conditional_size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
if ops.have_seen_ptr(self.heap_ptr()) {
0
} else {
self.unconditional_size_of(ops)
}
}
}
/// If a mutex is stored directly as a member of a data type that is being measured,
/// it is the unique owner of its contents and deserves to be measured.
///
/// If a mutex is stored inside of an Arc value as a member of a data type that is being measured,
/// the Arc will not be automatically measured so there is no risk of overcounting the mutex's
/// contents.
impl<T: MallocSizeOf> MallocSizeOf for std::sync::Mutex<T> {
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
(*self.lock().unwrap()).size_of(ops)
}
}
impl MallocSizeOf for smallbitvec::SmallBitVec {
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
if let Some(ptr) = self.heap_ptr() {
unsafe { ops.malloc_size_of(ptr) }
} else {
0
}
}
}
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::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)
}
}
impl MallocSizeOf for selectors::parser::AncestorHashes {
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
let selectors::parser::AncestorHashes { ref packed_hashes } = *self;
packed_hashes.size_of(ops)
}
}
impl<Impl: selectors::parser::SelectorImpl> MallocUnconditionalSizeOf
for selectors::parser::Selector<Impl>
where
Impl::NonTSPseudoClass: MallocSizeOf,
Impl::PseudoElement: MallocSizeOf,
{
fn unconditional_size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
let mut n = 0;
// It's OK to measure this ThinArc directly because it's the
// "primary" reference. (The secondary references are on the
// Stylist.)
n += unsafe { ops.malloc_size_of(self.thin_arc_heap_ptr()) };
for component in self.iter_raw_match_order() {
n += component.size_of(ops);
}
n
}
}
impl<Impl: selectors::parser::SelectorImpl> MallocUnconditionalSizeOf
for selectors::parser::SelectorList<Impl>
where
Impl::NonTSPseudoClass: MallocSizeOf,
Impl::PseudoElement: MallocSizeOf,
{
fn unconditional_size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
let mut n = 0;
// It's OK to measure this ThinArc directly because it's the "primary" reference. (The
// secondary references are on the Stylist.)
n += unsafe { ops.malloc_size_of(self.thin_arc_heap_ptr()) };
if self.len() > 1 {
for selector in self.slice().iter() {
n += selector.size_of(ops);
}
}
n
}
}
impl<Impl: selectors::parser::SelectorImpl> MallocUnconditionalSizeOf
for selectors::parser::Component<Impl>
where
Impl::NonTSPseudoClass: MallocSizeOf,
Impl::PseudoElement: MallocSizeOf,
{
fn unconditional_size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
use selectors::parser::Component;
match self {
Component::AttributeOther(ref attr_selector) => attr_selector.size_of(ops),
Component::Negation(ref components) => components.unconditional_size_of(ops),
Component::NonTSPseudoClass(ref pseudo) => (*pseudo).size_of(ops),
Component::Slotted(ref selector) | Component::Host(Some(ref selector)) => {
selector.unconditional_size_of(ops)
},
Component::Is(ref list) | Component::Where(ref list) => list.unconditional_size_of(ops),
Component::Has(ref relative_selectors) => relative_selectors.size_of(ops),
Component::NthOf(ref nth_of_data) => nth_of_data.size_of(ops),
Component::PseudoElement(ref pseudo) => (*pseudo).size_of(ops),
Component::Combinator(..) |
Component::ExplicitAnyNamespace |
Component::ExplicitNoNamespace |
Component::DefaultNamespace(..) |
Component::Namespace(..) |
Component::ExplicitUniversalType |
Component::LocalName(..) |
Component::ID(..) |
Component::Part(..) |
Component::Class(..) |
Component::AttributeInNoNamespaceExists { .. } |
Component::AttributeInNoNamespace { .. } |
Component::Root |
Component::Empty |
Component::Scope |
Component::ImplicitScope |
Component::ParentSelector |
Component::Nth(..) |
Component::Host(None) |
Component::RelativeSelectorAnchor |
Component::Invalid(..) => 0,
}
}
}
impl<Impl: selectors::parser::SelectorImpl> MallocSizeOf
for selectors::attr::AttrSelectorWithOptionalNamespace<Impl>
{
fn size_of(&self, _ops: &mut MallocSizeOfOps) -> usize {
0
}
}
impl MallocSizeOf for Void {
#[inline]
fn size_of(&self, _ops: &mut MallocSizeOfOps) -> usize {
void::unreachable(*self)
}
}
#[cfg(feature = "servo")]
impl<Static: string_cache::StaticAtomSet> MallocSizeOf for string_cache::Atom<Static> {
fn size_of(&self, _ops: &mut MallocSizeOfOps) -> usize {
0
}
}
/// 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::NonZeroU64);
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);
malloc_size_of_is_0!(cssparser::TokenSerializationType, cssparser::SourceLocation, cssparser::SourcePosition);
malloc_size_of_is_0!(selectors::OpaqueElement);
/// Measurable that defers to inner value and used to verify MallocSizeOf implementation in a
/// struct.
#[derive(Clone)]
pub struct Measurable<T: MallocSizeOf>(pub T);
impl<T: MallocSizeOf> Deref for Measurable<T> {
type Target = T;
fn deref(&self) -> &T {
&self.0
}
}
impl<T: MallocSizeOf> DerefMut for Measurable<T> {
fn deref_mut(&mut self) -> &mut T {
&mut self.0
}
}