Auto merge of #26120 - servo:layout-2020-non-opaque-style-data, r=SimonSapin

Remove postorder traversal from layout 2020 during styling

components/script/dom/bindings/trace.rs

@@ -97,7 +97,7 @@ use profile_traits::mem::ProfilerChan as MemProfilerChan;
 use profile_traits::time::ProfilerChan as TimeProfilerChan;
 use script_layout_interface::message::PendingRestyle;
 use script_layout_interface::rpc::LayoutRPC;
-use script_layout_interface::OpaqueStyleAndLayoutData;
+use script_layout_interface::StyleAndOpaqueLayoutData;
 use script_traits::serializable::BlobImpl;
 use script_traits::transferable::MessagePortImpl;
 use script_traits::{DocumentActivity, DrawAPaintImageResult};
@@ -508,7 +508,7 @@ unsafe_no_jsmanaged_fields!(StatusCode);
 unsafe_no_jsmanaged_fields!(SystemTime);
 unsafe_no_jsmanaged_fields!(Instant);
 unsafe_no_jsmanaged_fields!(RelativePos);
-unsafe_no_jsmanaged_fields!(OpaqueStyleAndLayoutData);
+unsafe_no_jsmanaged_fields!(StyleAndOpaqueLayoutData);
 unsafe_no_jsmanaged_fields!(PathBuf);
 unsafe_no_jsmanaged_fields!(DrawAPaintImageResult);
 unsafe_no_jsmanaged_fields!(DocumentId);

components/script/dom/element.rs

@@ -396,7 +396,7 @@ impl Element {
     /// style will be `None` for elements in a `display: none` subtree. otherwise, the element has a
     /// layout box iff it doesn't have `display: none`.
     pub fn style(&self) -> Option<Arc<ComputedValues>> {
-        window_from_node(self).style_query(self.upcast::<Node>().to_trusted_node_address())
+        self.upcast::<Node>().style()
     }
 
     // https://drafts.csswg.org/cssom-view/#css-layout-box

components/script/dom/node.rs

@@ -75,8 +75,9 @@ use malloc_size_of::{MallocSizeOf, MallocSizeOfOps};
 use msg::constellation_msg::{BrowsingContextId, PipelineId};
 use net_traits::image::base::{Image, ImageMetadata};
 use ref_slice::ref_slice;
+use script_layout_interface::message::QueryMsg;
 use script_layout_interface::{HTMLCanvasData, HTMLMediaData, LayoutElementType, LayoutNodeType};
-use script_layout_interface::{OpaqueStyleAndLayoutData, SVGSVGData, TrustedNodeAddress};
+use script_layout_interface::{SVGSVGData, StyleAndOpaqueLayoutData, TrustedNodeAddress};
 use script_traits::DocumentActivity;
 use script_traits::UntrustedNodeAddress;
 use selectors::matching::{matches_selector_list, MatchingContext, MatchingMode};
@@ -95,6 +96,7 @@ use std::ops::Range;
 use std::sync::Arc as StdArc;
 use style::context::QuirksMode;
 use style::dom::OpaqueNode;
+use style::properties::ComputedValues;
 use style::selector_parser::{SelectorImpl, SelectorParser};
 use style::stylesheets::Stylesheet;
 use uuid::Uuid;
@@ -152,8 +154,8 @@ pub struct Node {
     ///
     /// Must be sent back to the layout thread to be destroyed when this
     /// node is finalized.
-    #[ignore_malloc_size_of = "shrug"]
-    style_and_layout_data: UnsafeCell<Option<OpaqueStyleAndLayoutData>>,
+    #[ignore_malloc_size_of = "Unsafe cell"]
+    style_and_layout_data: UnsafeCell<Option<Box<StyleAndOpaqueLayoutData>>>,
 }
 
 bitflags! {
@@ -1229,6 +1231,23 @@ impl Node {
             _ => false,
         }
     }
+
+    #[allow(unsafe_code)]
+    pub fn style(&self) -> Option<Arc<ComputedValues>> {
+        if !window_from_node(self).layout_reflow(QueryMsg::StyleQuery) {
+            return None;
+        }
+        unsafe {
+            (*self.style_and_layout_data.get()).as_ref().map(|data| {
+                data.style_data
+                    .element_data
+                    .borrow()
+                    .styles
+                    .primary()
+                    .clone()
+            })
+        }
+    }
 }
 
 /// Iterate through `nodes` until we find a `Node` that is not in `not_in`
@@ -1282,9 +1301,9 @@ pub trait LayoutNodeHelpers<'dom> {
 
     fn children_count(self) -> u32;
 
-    fn get_style_and_layout_data(self) -> Option<&'dom OpaqueStyleAndLayoutData>;
-    unsafe fn init_style_and_layout_data(self, data: OpaqueStyleAndLayoutData);
-    unsafe fn take_style_and_layout_data(self) -> OpaqueStyleAndLayoutData;
+    fn get_style_and_opaque_layout_data(self) -> Option<&'dom StyleAndOpaqueLayoutData>;
+    unsafe fn init_style_and_opaque_layout_data(self, data: Box<StyleAndOpaqueLayoutData>);
+    unsafe fn take_style_and_opaque_layout_data(self) -> Box<StyleAndOpaqueLayoutData>;
 
     fn text_content(self) -> Cow<'dom, str>;
     fn selection(self) -> Option<Range<usize>>;
@@ -1410,13 +1429,13 @@ impl<'dom> LayoutNodeHelpers<'dom> for LayoutDom<'dom, Node> {
 
     #[inline]
     #[allow(unsafe_code)]
-    fn get_style_and_layout_data(self) -> Option<&'dom OpaqueStyleAndLayoutData> {
-        unsafe { (*self.unsafe_get().style_and_layout_data.get()).as_ref() }
+    fn get_style_and_opaque_layout_data(self) -> Option<&'dom StyleAndOpaqueLayoutData> {
+        unsafe { (*self.unsafe_get().style_and_layout_data.get()).as_deref() }
     }
 
     #[inline]
     #[allow(unsafe_code)]
-    unsafe fn init_style_and_layout_data(self, val: OpaqueStyleAndLayoutData) {
+    unsafe fn init_style_and_opaque_layout_data(self, val: Box<StyleAndOpaqueLayoutData>) {
         let data = &mut *self.unsafe_get().style_and_layout_data.get();
         debug_assert!(data.is_none());
         *data = Some(val);
@@ -1424,7 +1443,7 @@ impl<'dom> LayoutNodeHelpers<'dom> for LayoutDom<'dom, Node> {
 
     #[inline]
     #[allow(unsafe_code)]
-    unsafe fn take_style_and_layout_data(self) -> OpaqueStyleAndLayoutData {
+    unsafe fn take_style_and_opaque_layout_data(self) -> Box<StyleAndOpaqueLayoutData> {
         (*self.unsafe_get().style_and_layout_data.get())
             .take()
             .unwrap()

components/script/dom/window.rs

@@ -131,7 +131,7 @@ use style::dom::OpaqueNode;
 use style::error_reporting::{ContextualParseError, ParseErrorReporter};
 use style::media_queries;
 use style::parser::ParserContext as CssParserContext;
-use style::properties::{ComputedValues, PropertyId};
+use style::properties::PropertyId;
 use style::selector_parser::PseudoElement;
 use style::str::HTML_SPACE_CHARACTERS;
 use style::stylesheets::CssRuleType;
@@ -1904,13 +1904,6 @@ impl Window {
         (element, response.rect)
     }
 
-    pub fn style_query(&self, node: TrustedNodeAddress) -> Option<servo_arc::Arc<ComputedValues>> {
-        if !self.layout_reflow(QueryMsg::StyleQuery(node)) {
-            return None;
-        }
-        self.layout_rpc.style().0
-    }
-
     pub fn text_index_query(
         &self,
         node: &Node,
@@ -2461,7 +2454,7 @@ fn debug_reflow_events(id: PipelineId, reflow_goal: &ReflowGoal, reason: &Reflow
             &QueryMsg::NodeScrollIdQuery(_n) => "\tNodeScrollIdQuery",
             &QueryMsg::ResolvedStyleQuery(_, _, _) => "\tResolvedStyleQuery",
             &QueryMsg::OffsetParentQuery(_n) => "\tOffsetParentQuery",
-            &QueryMsg::StyleQuery(_n) => "\tStyleQuery",
+            &QueryMsg::StyleQuery => "\tStyleQuery",
             &QueryMsg::TextIndexQuery(..) => "\tTextIndexQuery",
             &QueryMsg::ElementInnerTextQuery(_) => "\tElementInnerTextQuery",
             &QueryMsg::InnerWindowDimensionsQuery(_) => "\tInnerWindowDimensionsQuery",