Bug 1325734 - Parameterize the style traversal on TElement instead of TNode. r=emilio

This works around the issue described in https://github.com/rust-lang/rust/issues/38917
This commit is contained in:
Bobby Holley 2017-01-07 22:41:55 -08:00
parent 962a4a79bb
commit 3060865577
6 changed files with 62 additions and 59 deletions

View file

@ -14,7 +14,7 @@ use script_layout_interface::wrapper_traits::{LayoutNode, ThreadSafeLayoutNode};
use servo_config::opts;
use style::context::{SharedStyleContext, StyleContext};
use style::data::ElementData;
use style::dom::{TElement, TNode};
use style::dom::{NodeInfo, TElement, TNode};
use style::selector_parser::RestyleDamage;
use style::servo::restyle_damage::{BUBBLE_ISIZES, REFLOW, REFLOW_OUT_OF_FLOW, REPAINT};
use style::traversal::{DomTraversal, recalc_style_at};
@ -48,14 +48,14 @@ impl RecalcStyleAndConstructFlows {
}
#[allow(unsafe_code)]
impl<N> DomTraversal<N> for RecalcStyleAndConstructFlows
where N: LayoutNode + TNode,
N::ConcreteElement: TElement
impl<E> DomTraversal<E> for RecalcStyleAndConstructFlows
where E: TElement,
E::ConcreteNode: LayoutNode,
{
type ThreadLocalContext = ScopedThreadLocalLayoutContext<N::ConcreteElement>;
type ThreadLocalContext = ScopedThreadLocalLayoutContext<E>;
fn process_preorder(&self, traversal_data: &mut PerLevelTraversalData,
thread_local: &mut Self::ThreadLocalContext, node: N) {
thread_local: &mut Self::ThreadLocalContext, node: E::ConcreteNode) {
// FIXME(pcwalton): Stop allocating here. Ideally this should just be
// done by the HTML parser.
node.initialize_data();
@ -71,12 +71,12 @@ impl<N> DomTraversal<N> for RecalcStyleAndConstructFlows
}
}
fn process_postorder(&self, thread_local: &mut Self::ThreadLocalContext, node: N) {
fn process_postorder(&self, thread_local: &mut Self::ThreadLocalContext, node: E::ConcreteNode) {
let context = LayoutContext::new(&self.shared);
construct_flows_at(&context, thread_local, node);
}
fn text_node_needs_traversal(node: N) -> bool {
fn text_node_needs_traversal(node: E::ConcreteNode) -> bool {
// Text nodes never need styling. However, there are two cases they may need
// flow construction:
// (1) They child doesn't yet have layout data (preorder traversal initializes it).
@ -85,12 +85,12 @@ impl<N> DomTraversal<N> for RecalcStyleAndConstructFlows
node.parent_node().unwrap().to_threadsafe().restyle_damage() != RestyleDamage::empty()
}
unsafe fn ensure_element_data(element: &N::ConcreteElement) -> &AtomicRefCell<ElementData> {
unsafe fn ensure_element_data(element: &E) -> &AtomicRefCell<ElementData> {
element.as_node().initialize_data();
element.get_data().unwrap()
}
unsafe fn clear_element_data(element: &N::ConcreteElement) {
unsafe fn clear_element_data(element: &E) {
element.as_node().clear_data();
}

View file

@ -1157,9 +1157,9 @@ impl LayoutThread {
let dom_depth = Some(0); // This is always the root node.
let token = {
let stylist = &<RecalcStyleAndConstructFlows as
DomTraversal<ServoLayoutNode>>::shared_context(&traversal).stylist;
DomTraversal<ServoLayoutElement>>::shared_context(&traversal).stylist;
<RecalcStyleAndConstructFlows as
DomTraversal<ServoLayoutNode>>::pre_traverse(element, stylist, /* skip_root = */ false)
DomTraversal<ServoLayoutElement>>::pre_traverse(element, stylist, /* skip_root = */ false)
};
if token.should_traverse() {
@ -1171,11 +1171,11 @@ impl LayoutThread {
// Perform CSS selector matching and flow construction.
if let (true, Some(pool)) = (self.parallel_flag, self.parallel_traversal.as_mut()) {
// Parallel mode
parallel::traverse_dom::<ServoLayoutNode, RecalcStyleAndConstructFlows>(
parallel::traverse_dom::<ServoLayoutElement, RecalcStyleAndConstructFlows>(
&traversal, element, dom_depth, token, pool);
} else {
// Sequential mode
sequential::traverse_dom::<ServoLayoutNode, RecalcStyleAndConstructFlows>(
sequential::traverse_dom::<ServoLayoutElement, RecalcStyleAndConstructFlows>(
&traversal, element, token);
}
});

View file

@ -26,12 +26,12 @@ impl RecalcStyleOnly {
}
}
impl<'ln> DomTraversal<GeckoNode<'ln>> for RecalcStyleOnly {
type ThreadLocalContext = ThreadLocalStyleContext<GeckoElement<'ln>>;
impl<'le> DomTraversal<GeckoElement<'le>> for RecalcStyleOnly {
type ThreadLocalContext = ThreadLocalStyleContext<GeckoElement<'le>>;
fn process_preorder(&self, traversal_data: &mut PerLevelTraversalData,
thread_local: &mut Self::ThreadLocalContext,
node: GeckoNode<'ln>)
node: GeckoNode<'le>)
{
if node.is_element() {
let el = node.as_element().unwrap();
@ -44,18 +44,18 @@ impl<'ln> DomTraversal<GeckoNode<'ln>> for RecalcStyleOnly {
}
}
fn process_postorder(&self, _: &mut Self::ThreadLocalContext, _: GeckoNode<'ln>) {
fn process_postorder(&self, _: &mut Self::ThreadLocalContext, _: GeckoNode<'le>) {
unreachable!();
}
/// We don't use the post-order traversal for anything.
fn needs_postorder_traversal() -> bool { false }
unsafe fn ensure_element_data<'a>(element: &'a GeckoElement<'ln>) -> &'a AtomicRefCell<ElementData> {
unsafe fn ensure_element_data<'a>(element: &'a GeckoElement<'le>) -> &'a AtomicRefCell<ElementData> {
element.ensure_data()
}
unsafe fn clear_element_data<'a>(element: &'a GeckoElement<'ln>) {
unsafe fn clear_element_data<'a>(element: &'a GeckoElement<'le>) {
element.clear_data()
}

View file

@ -37,13 +37,13 @@ pub const CHUNK_SIZE: usize = 64;
/// A parallel top down traversal, generic over `D`.
#[allow(unsafe_code)]
pub fn traverse_dom<N, D>(traversal: &D,
root: N::ConcreteElement,
pub fn traverse_dom<E, D>(traversal: &D,
root: E,
known_root_dom_depth: Option<usize>,
token: PreTraverseToken,
queue: &rayon::ThreadPool)
where N: TNode,
D: DomTraversal<N>,
where E: TElement,
D: DomTraversal<E>,
{
if opts::get().style_sharing_stats {
STYLE_SHARING_CACHE_HITS.store(0, Ordering::SeqCst);
@ -91,14 +91,14 @@ pub fn traverse_dom<N, D>(traversal: &D,
/// A parallel top-down DOM traversal.
#[inline(always)]
#[allow(unsafe_code)]
fn top_down_dom<'a, 'scope, N, D>(nodes: &'a [SendNode<N>],
fn top_down_dom<'a, 'scope, E, D>(nodes: &'a [SendNode<E::ConcreteNode>],
root: OpaqueNode,
mut traversal_data: PerLevelTraversalData,
scope: &'a rayon::Scope<'scope>,
traversal: &'scope D,
tls: &'scope ScopedTLS<'scope, D::ThreadLocalContext>)
where N: TNode + 'scope,
D: DomTraversal<N>,
where E: TElement + 'scope,
D: DomTraversal<E>,
{
let mut discovered_child_nodes = vec![];
{
@ -140,13 +140,13 @@ fn top_down_dom<'a, 'scope, N, D>(nodes: &'a [SendNode<N>],
traverse_nodes(discovered_child_nodes, root, traversal_data, scope, traversal, tls);
}
fn traverse_nodes<'a, 'scope, N, D>(nodes: Vec<SendNode<N>>, root: OpaqueNode,
fn traverse_nodes<'a, 'scope, E, D>(nodes: Vec<SendNode<E::ConcreteNode>>, root: OpaqueNode,
traversal_data: PerLevelTraversalData,
scope: &'a rayon::Scope<'scope>,
traversal: &'scope D,
tls: &'scope ScopedTLS<'scope, D::ThreadLocalContext>)
where N: TNode + 'scope,
D: DomTraversal<N>,
where E: TElement + 'scope,
D: DomTraversal<E>,
{
if nodes.is_empty() {
return;
@ -182,12 +182,12 @@ fn traverse_nodes<'a, 'scope, N, D>(nodes: Vec<SendNode<N>>, root: OpaqueNode,
///
/// The only communication between siblings is that they both
/// fetch-and-subtract the parent's children count.
fn bottom_up_dom<N, D>(traversal: &D,
fn bottom_up_dom<E, D>(traversal: &D,
thread_local: &mut D::ThreadLocalContext,
root: OpaqueNode,
mut node: N)
where N: TNode,
D: DomTraversal<N>,
mut node: E::ConcreteNode)
where E: TElement,
D: DomTraversal<E>,
{
loop {
// Perform the appropriate operation.

View file

@ -10,18 +10,18 @@ use dom::{TElement, TNode};
use traversal::{DomTraversal, PerLevelTraversalData, PreTraverseToken};
/// Do a sequential DOM traversal for layout or styling, generic over `D`.
pub fn traverse_dom<N, D>(traversal: &D,
root: N::ConcreteElement,
pub fn traverse_dom<E, D>(traversal: &D,
root: E,
token: PreTraverseToken)
where N: TNode,
D: DomTraversal<N>,
where E: TElement,
D: DomTraversal<E>,
{
debug_assert!(token.should_traverse());
fn doit<N, D>(traversal: &D, traversal_data: &mut PerLevelTraversalData,
thread_local: &mut D::ThreadLocalContext, node: N)
where N: TNode,
D: DomTraversal<N>
fn doit<E, D>(traversal: &D, traversal_data: &mut PerLevelTraversalData,
thread_local: &mut D::ThreadLocalContext, node: E::ConcreteNode)
where E: TElement,
D: DomTraversal<E>
{
traversal.process_preorder(traversal_data, thread_local, node);
if let Some(el) = node.as_element() {

View file

@ -9,11 +9,10 @@
use atomic_refcell::{AtomicRefCell, AtomicRefMut};
use context::{SharedStyleContext, StyleContext};
use data::{ElementData, ElementStyles, StoredRestyleHint};
use dom::{TElement, TNode};
use dom::{NodeInfo, TElement, TNode};
use matching::{MatchMethods, StyleSharingResult};
use restyle_hints::{RESTYLE_DESCENDANTS, RESTYLE_SELF};
use selector_parser::RestyleDamage;
use selectors::Element;
use servo_config::opts;
use std::mem;
use std::sync::atomic::{AtomicUsize, ATOMIC_USIZE_INIT, Ordering};
@ -72,7 +71,7 @@ impl LogBehavior {
/// A DOM Traversal trait, that is used to generically implement styling for
/// Gecko and Servo.
pub trait DomTraversal<N: TNode> : Sync {
pub trait DomTraversal<E: TElement> : Sync {
/// The thread-local context, used to store non-thread-safe stuff that needs
/// to be used in the traversal, and of which we use one per worker, like
/// the bloom filter, for example.
@ -80,12 +79,15 @@ pub trait DomTraversal<N: TNode> : Sync {
/// Process `node` on the way down, before its children have been processed.
fn process_preorder(&self, data: &mut PerLevelTraversalData,
thread_local: &mut Self::ThreadLocalContext, node: N);
thread_local: &mut Self::ThreadLocalContext,
node: E::ConcreteNode);
/// Process `node` on the way up, after its children have been processed.
///
/// This is only executed if `needs_postorder_traversal` returns true.
fn process_postorder(&self, thread_local: &mut Self::ThreadLocalContext, node: N);
fn process_postorder(&self,
thread_local: &mut Self::ThreadLocalContext,
node: E::ConcreteNode);
/// Boolean that specifies whether a bottom up traversal should be
/// performed.
@ -99,8 +101,7 @@ pub trait DomTraversal<N: TNode> : Sync {
///
/// The unstyled_children_only parameter is used in Gecko to style newly-
/// appended children without restyling the parent.
fn pre_traverse(root: N::ConcreteElement, stylist: &Stylist,
unstyled_children_only: bool)
fn pre_traverse(root: E, stylist: &Stylist, unstyled_children_only: bool)
-> PreTraverseToken
{
if unstyled_children_only {
@ -132,10 +133,13 @@ pub trait DomTraversal<N: TNode> : Sync {
/// Returns true if traversal should visit a text node. The style system never
/// processes text nodes, but Servo overrides this to visit them for flow
/// construction when necessary.
fn text_node_needs_traversal(node: N) -> bool { debug_assert!(node.is_text_node()); false }
fn text_node_needs_traversal(node: E::ConcreteNode) -> bool {
debug_assert!(node.is_text_node());
false
}
/// Returns true if traversal is needed for the given node and subtree.
fn node_needs_traversal(node: N) -> bool {
fn node_needs_traversal(node: E::ConcreteNode) -> bool {
// Non-incremental layout visits every node.
if cfg!(feature = "servo") && opts::get().nonincremental_layout {
return true;
@ -189,8 +193,7 @@ pub trait DomTraversal<N: TNode> : Sync {
///
/// This may be called multiple times when processing an element, so we pass
/// a parameter to keep the logs tidy.
fn should_traverse_children(parent: N::ConcreteElement, parent_data: &ElementData,
log: LogBehavior) -> bool
fn should_traverse_children(parent: E, parent_data: &ElementData, log: LogBehavior) -> bool
{
// See the comment on `cascade_node` for why we allow this on Gecko.
debug_assert!(cfg!(feature = "gecko") || parent_data.has_current_styles());
@ -234,7 +237,7 @@ pub trait DomTraversal<N: TNode> : Sync {
/// Helper for the traversal implementations to select the children that
/// should be enqueued for processing.
fn traverse_children<F: FnMut(N)>(parent: N::ConcreteElement, mut f: F)
fn traverse_children<F: FnMut(E::ConcreteNode)>(parent: E, mut f: F)
{
// Check if we're allowed to traverse past this element.
if !Self::should_traverse_children(parent, &parent.borrow_data().unwrap(), MayLog) {
@ -260,13 +263,13 @@ pub trait DomTraversal<N: TNode> : Sync {
///
/// This is only safe to call in top-down traversal before processing the
/// children of |element|.
unsafe fn ensure_element_data(element: &N::ConcreteElement) -> &AtomicRefCell<ElementData>;
unsafe fn ensure_element_data(element: &E) -> &AtomicRefCell<ElementData>;
/// Clears the ElementData attached to this element, if any.
///
/// This is only safe to call in top-down traversal before processing the
/// children of |element|.
unsafe fn clear_element_data(element: &N::ConcreteElement);
unsafe fn clear_element_data(element: &E);
/// Return the shared style context common to all worker threads.
fn shared_context(&self) -> &SharedStyleContext;
@ -364,7 +367,7 @@ pub fn recalc_style_at<E, D>(traversal: &D,
element: E,
mut data: &mut AtomicRefMut<ElementData>)
where E: TElement,
D: DomTraversal<E::ConcreteNode>
D: DomTraversal<E>
{
debug_assert!(data.as_restyle().map_or(true, |r| r.snapshot.is_none()),
"Snapshots should be expanded by the caller");
@ -411,7 +414,7 @@ fn compute_style<E, D>(_traversal: &D,
element: E,
mut data: &mut AtomicRefMut<ElementData>) -> bool
where E: TElement,
D: DomTraversal<E::ConcreteNode>,
D: DomTraversal<E>,
{
let shared_context = context.shared;
// Ensure the bloom filter is up to date.
@ -498,7 +501,7 @@ fn preprocess_children<E, D>(traversal: &D,
mut propagated_hint: StoredRestyleHint,
parent_inherited_style_changed: bool)
where E: TElement,
D: DomTraversal<E::ConcreteNode>
D: DomTraversal<E>
{
// Loop over all the children.
for child in element.as_node().children() {