Skip to content

Commit

Permalink
Move thread state checks out of generic methods to reduce generated c…
Browse files Browse the repository at this point in the history 
…ode duplication.
  • Loading branch information
@jdm
jdm committed Jun 5, 2020
1 parent 6dc4488 commit ec0b5d5
Show file tree
Hide file tree
Showing 2 changed files with 41 additions and 33 deletions.
12 changes: 6 additions & 6 deletions components/script/dom/bindings/cell.rs
View file
Expand Up @@ -4,14 +4,14 @@

//! A shareable mutable container for the DOM.

use crate::dom::bindings::root::{assert_in_layout, assert_in_script};
#[cfg(feature = "refcell_backtrace")]
pub use accountable_refcell::{ref_filter_map, Ref, RefCell, RefMut};
#[cfg(not(feature = "refcell_backtrace"))]
pub use ref_filter_map::ref_filter_map;
use std::cell::{BorrowError, BorrowMutError};
#[cfg(not(feature = "refcell_backtrace"))]
pub use std::cell::{Ref, RefCell, RefMut};
use style::thread_state::{self, ThreadState};

/// A mutable field in the DOM.
///
Expand All @@ -31,7 +31,7 @@ impl<T> DomRefCell<T> {
/// For use in the layout thread only.
#[allow(unsafe_code)]
pub unsafe fn borrow_for_layout(&self) -> &T {
debug_assert!(thread_state::get().is_layout());
assert_in_layout();
self.value
.try_borrow_unguarded()
.expect("cell is mutably borrowed")
Expand All @@ -41,15 +41,15 @@ impl<T> DomRefCell<T> {
///
#[allow(unsafe_code)]
pub unsafe fn borrow_for_script_deallocation(&self) -> &mut T {
debug_assert!(thread_state::get().contains(ThreadState::SCRIPT));
assert_in_script();
&mut *self.value.as_ptr()
}

/// Mutably borrow a cell for layout. Ideally this would use
/// `RefCell::try_borrow_mut_unguarded` but that doesn't exist yet.
#[allow(unsafe_code)]
pub unsafe fn borrow_mut_for_layout(&self) -> &mut T {
debug_assert!(thread_state::get().is_layout());
assert_in_layout();
&mut *self.value.as_ptr()
}
}
Expand Down Expand Up @@ -105,7 +105,7 @@ impl<T> DomRefCell<T> {
///
/// Panics if this is called off the script thread.
pub fn try_borrow(&self) -> Result<Ref<T>, BorrowError> {
debug_assert!(thread_state::get().is_script());
assert_in_script();
self.value.try_borrow()
}

Expand All @@ -120,7 +120,7 @@ impl<T> DomRefCell<T> {
///
/// Panics if this is called off the script thread.
pub fn try_borrow_mut(&self) -> Result<RefMut<T>, BorrowMutError> {
debug_assert!(thread_state::get().is_script());
assert_in_script();
self.value.try_borrow_mut()
}
}
62 changes: 35 additions & 27 deletions components/script/dom/bindings/root.rs
View file
Expand Up @@ -64,7 +64,7 @@ where
#[allow(unrooted_must_root)]
pub unsafe fn new(value: T) -> Self {
unsafe fn add_to_root_list(object: *const dyn JSTraceable) -> *const RootCollection {
debug_assert!(thread_state::get().is_script());
assert_in_script();
STACK_ROOTS.with(|ref root_list| {
let root_list = &*root_list.get().unwrap();
root_list.root(object);
Expand Down Expand Up @@ -137,7 +137,7 @@ where
type Target = <T as Deref>::Target;

fn deref(&self) -> &Self::Target {
debug_assert!(thread_state::get().is_script());
assert_in_script();
&self.value
}
}
Expand Down Expand Up @@ -251,21 +251,21 @@ impl<'a> Drop for ThreadLocalStackRoots<'a> {
impl RootCollection {
/// Create an empty collection of roots
pub fn new() -> RootCollection {
debug_assert!(thread_state::get().is_script());
assert_in_script();
RootCollection {
roots: UnsafeCell::new(vec![]),
}
}

/// Starts tracking a trace object.
unsafe fn root(&self, object: *const dyn JSTraceable) {
debug_assert!(thread_state::get().is_script());
assert_in_script();
(*self.roots.get()).push(object);
}

/// Stops tracking a trace object, asserting if it isn't found.
unsafe fn unroot(&self, object: *const dyn JSTraceable) {
debug_assert!(thread_state::get().is_script());
assert_in_script();
let roots = &mut *self.roots.get();
match roots
.iter()
Expand Down Expand Up @@ -333,7 +333,7 @@ impl<T> MallocSizeOf for Dom<T> {
impl<T> Dom<T> {
/// Returns `LayoutDom<T>` containing the same pointer.
pub unsafe fn to_layout(&self) -> LayoutDom<T> {
debug_assert!(thread_state::get().is_layout());
assert_in_layout();
LayoutDom {
value: self.ptr.as_ref(),
}
Expand All @@ -344,7 +344,7 @@ impl<T: DomObject> Dom<T> {
/// Create a Dom<T> from a &T
#[allow(unrooted_must_root)]
pub fn from_ref(obj: &T) -> Dom<T> {
debug_assert!(thread_state::get().is_script());
assert_in_script();
Dom {
ptr: ptr::NonNull::from(obj),
}
Expand All @@ -355,7 +355,7 @@ impl<T: DomObject> Deref for Dom<T> {
type Target = T;

fn deref(&self) -> &T {
debug_assert!(thread_state::get().is_script());
assert_in_script();
// We can only have &Dom<T> from a rooted thing, so it's safe to deref
// it to &T.
unsafe { &*self.ptr.as_ptr() }
Expand Down Expand Up @@ -432,7 +432,7 @@ where
U: Castable,
T: DerivedFrom<U>,
{
debug_assert!(thread_state::get().is_layout());
assert_in_layout();
LayoutDom {
value: self.value.upcast::<U>(),
}
Expand All @@ -443,7 +443,7 @@ where
where
U: DerivedFrom<T>,
{
debug_assert!(thread_state::get().is_layout());
assert_in_layout();
self.value.downcast::<U>().map(|value| LayoutDom { value })
}

Expand All @@ -452,7 +452,7 @@ where
where
U: DerivedFrom<T>,
{
debug_assert!(thread_state::get().is_layout());
assert_in_layout();
self.value.is::<U>()
}
}
Expand All @@ -463,7 +463,7 @@ where
{
/// Get the reflector.
pub unsafe fn get_jsobject(&self) -> *mut JSObject {
debug_assert!(thread_state::get().is_layout());
assert_in_layout();
self.value.reflector().get_jsobject().get()
}
}
Expand Down Expand Up @@ -508,7 +508,7 @@ impl<T> Clone for Dom<T> {
#[inline]
#[allow(unrooted_must_root)]
fn clone(&self) -> Self {
debug_assert!(thread_state::get().is_script());
assert_in_script();
Dom {
ptr: self.ptr.clone(),
}
Expand All @@ -518,7 +518,7 @@ impl<T> Clone for Dom<T> {
impl<T> Clone for LayoutDom<'_, T> {
#[inline]
fn clone(&self) -> Self {
debug_assert!(thread_state::get().is_layout());
assert_in_layout();
LayoutDom { value: self.value }
}
}
Expand All @@ -527,7 +527,7 @@ impl LayoutDom<'_, Node> {
/// Create a new JS-owned value wrapped from an address known to be a
/// `Node` pointer.
pub unsafe fn from_trusted_node_address(inner: TrustedNodeAddress) -> Self {
debug_assert!(thread_state::get().is_layout());
assert_in_layout();
let TrustedNodeAddress(addr) = inner;
LayoutDom {
value: &*(addr as *const Node),
Expand All @@ -549,23 +549,23 @@ pub struct MutDom<T: DomObject> {
impl<T: DomObject> MutDom<T> {
/// Create a new `MutDom`.
pub fn new(initial: &T) -> MutDom<T> {
debug_assert!(thread_state::get().is_script());
assert_in_script();
MutDom {
val: UnsafeCell::new(Dom::from_ref(initial)),
}
}

/// Set this `MutDom` to the given value.
pub fn set(&self, val: &T) {
debug_assert!(thread_state::get().is_script());
assert_in_script();
unsafe {
*self.val.get() = Dom::from_ref(val);
}
}

/// Get the value in this `MutDom`.
pub fn get(&self) -> DomRoot<T> {
debug_assert!(thread_state::get().is_script());
assert_in_script();
unsafe { DomRoot::from_ref(&*ptr::read(self.val.get())) }
}
}
Expand All @@ -589,6 +589,14 @@ impl<T: DomObject + PartialEq> PartialEq<T> for MutDom<T> {
}
}

pub(crate) fn assert_in_script() {
debug_assert!(thread_state::get().is_script());
}

pub(crate) fn assert_in_layout() {
debug_assert!(thread_state::get().is_layout());
}

/// A holder that provides interior mutability for GC-managed values such as
/// `Dom<T>`, with nullability represented by an enclosing Option wrapper.
/// Essentially a `Cell<Option<Dom<T>>>`, but safer.
Expand All @@ -604,7 +612,7 @@ pub struct MutNullableDom<T: DomObject> {
impl<T: DomObject> MutNullableDom<T> {
/// Create a new `MutNullableDom`.
pub fn new(initial: Option<&T>) -> MutNullableDom<T> {
debug_assert!(thread_state::get().is_script());
assert_in_script();
MutNullableDom {
ptr: UnsafeCell::new(initial.map(Dom::from_ref)),
}
Expand All @@ -616,7 +624,7 @@ impl<T: DomObject> MutNullableDom<T> {
where
F: FnOnce() -> DomRoot<T>,
{
debug_assert!(thread_state::get().is_script());
assert_in_script();
match self.get() {
Some(inner) => inner,
None => {
Expand All @@ -631,20 +639,20 @@ impl<T: DomObject> MutNullableDom<T> {
/// For use by layout, which can't use safe types like Temporary.
#[allow(unrooted_must_root)]
pub unsafe fn get_inner_as_layout(&self) -> Option<LayoutDom<T>> {
debug_assert!(thread_state::get().is_layout());
assert_in_layout();
(*self.ptr.get()).as_ref().map(|js| js.to_layout())
}

/// Get a rooted value out of this object
#[allow(unrooted_must_root)]
pub fn get(&self) -> Option<DomRoot<T>> {
debug_assert!(thread_state::get().is_script());
assert_in_script();
unsafe { ptr::read(self.ptr.get()).map(|o| DomRoot::from_ref(&*o)) }
}

/// Set this `MutNullableDom` to the given value.
pub fn set(&self, val: Option<&T>) {
debug_assert!(thread_state::get().is_script());
assert_in_script();
unsafe {
*self.ptr.get() = val.map(|p| Dom::from_ref(p));
}
Expand Down Expand Up @@ -673,7 +681,7 @@ impl<'a, T: DomObject> PartialEq<Option<&'a T>> for MutNullableDom<T> {
impl<T: DomObject> Default for MutNullableDom<T> {
#[allow(unrooted_must_root)]
fn default() -> MutNullableDom<T> {
debug_assert!(thread_state::get().is_script());
assert_in_script();
MutNullableDom {
ptr: UnsafeCell::new(None),
}
Expand Down Expand Up @@ -709,15 +717,15 @@ where
where
F: FnOnce() -> DomRoot<T>,
{
debug_assert!(thread_state::get().is_script());
assert_in_script();
&self.ptr.init_once(|| Dom::from_ref(&cb()))
}
}

impl<T: DomObject> Default for DomOnceCell<T> {
#[allow(unrooted_must_root)]
fn default() -> DomOnceCell<T> {
debug_assert!(thread_state::get().is_script());
assert_in_script();
DomOnceCell {
ptr: OnceCell::new(),
}
Expand Down Expand Up @@ -747,7 +755,7 @@ where
/// Returns a reference to the interior of this JS object. The fact
/// that this is unsafe is what necessitates the layout wrappers.
pub unsafe fn unsafe_get(self) -> &'dom T {
debug_assert!(thread_state::get().is_layout());
assert_in_layout();
self.value
}

Expand Down

0 comments on commit ec0b5d5

Please sign in to comment.