Auto merge of #19493 - emilio:chrome-perf, r=xidorn,Manishearth

style: Some stylo-chrome perf tweaks.

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components/style/gecko/generated/bindings.rs

@@ -528,14 +528,10 @@ extern "C" {
  pub fn Gecko_LoadStyleSheet ( loader : * mut Loader , parent : * mut ServoStyleSheet , reusable_sheets : * mut LoaderReusableStyleSheets , base_url_data : * mut RawGeckoURLExtraData , url_bytes : * const u8 , url_length : u32 , media_list : RawServoMediaListStrong , ) -> * mut ServoStyleSheet ; 
 } extern "C" {
  pub fn Gecko_ElementState ( element : RawGeckoElementBorrowed , ) -> u64 ; 
-} extern "C" {
- pub fn Gecko_DocumentState ( aDocument : * const nsIDocument , ) -> u64 ; 
 } extern "C" {
  pub fn Gecko_IsRootElement ( element : RawGeckoElementBorrowed , ) -> bool ; 
 } extern "C" {
  pub fn Gecko_MatchesElement ( type_ : CSSPseudoClassType , element : RawGeckoElementBorrowed , ) -> bool ; 
-} extern "C" {
- pub fn Gecko_Namespace ( element : RawGeckoElementBorrowed , ) -> * mut nsAtom ; 
 } extern "C" {
  pub fn Gecko_MatchLang ( element : RawGeckoElementBorrowed , override_lang : * mut nsAtom , has_override_lang : bool , value : * const u16 , ) -> bool ; 
 } extern "C" {
@@ -600,8 +596,6 @@ extern "C" {
  pub fn Gecko_IsPrivateBrowsingEnabled ( aDoc : * const nsIDocument , ) -> bool ; 
 } extern "C" {
  pub fn Gecko_GetAnimationRule ( aElementOrPseudo : RawGeckoElementBorrowed , aCascadeLevel : EffectCompositor_CascadeLevel , aAnimationValues : RawServoAnimationValueMapBorrowedMut , ) -> bool ; 
-} extern "C" {
- pub fn Gecko_GetSMILOverrideDeclarationBlock ( element : RawGeckoElementBorrowed , ) -> RawServoDeclarationBlockStrongBorrowedOrNull ; 
 } extern "C" {
  pub fn Gecko_StyleAnimationsEquals ( arg1 : RawGeckoStyleAnimationListBorrowed , arg2 : RawGeckoStyleAnimationListBorrowed , ) -> bool ; 
 } extern "C" {

components/style/gecko/wrapper.rs

@@ -29,9 +29,9 @@ use gecko::selector_parser::{SelectorImpl, NonTSPseudoClass, PseudoElement};
 use gecko::snapshot_helpers;
 use gecko_bindings::bindings;
 use gecko_bindings::bindings::{Gecko_ConstructStyleChildrenIterator, Gecko_DestroyStyleChildrenIterator};
-use gecko_bindings::bindings::{Gecko_DocumentState, Gecko_ElementState, Gecko_GetDocumentLWTheme};
+use gecko_bindings::bindings::{Gecko_ElementState, Gecko_GetDocumentLWTheme};
 use gecko_bindings::bindings::{Gecko_GetLastChild, Gecko_GetNextStyleChild};
-use gecko_bindings::bindings::{Gecko_IsRootElement, Gecko_MatchesElement, Gecko_Namespace};
+use gecko_bindings::bindings::{Gecko_IsRootElement, Gecko_MatchesElement};
 use gecko_bindings::bindings::{Gecko_SetNodeFlags, Gecko_UnsetNodeFlags};
 use gecko_bindings::bindings::Gecko_ClassOrClassList;
 use gecko_bindings::bindings::Gecko_ElementHasAnimations;
@@ -41,7 +41,6 @@ use gecko_bindings::bindings::Gecko_GetActiveLinkAttrDeclarationBlock;
 use gecko_bindings::bindings::Gecko_GetAnimationRule;
 use gecko_bindings::bindings::Gecko_GetExtraContentStyleDeclarations;
 use gecko_bindings::bindings::Gecko_GetHTMLPresentationAttrDeclarationBlock;
-use gecko_bindings::bindings::Gecko_GetSMILOverrideDeclarationBlock;
 use gecko_bindings::bindings::Gecko_GetStyleAttrDeclarationBlock;
 use gecko_bindings::bindings::Gecko_GetUnvisitedLinkAttrDeclarationBlock;
 use gecko_bindings::bindings::Gecko_GetVisitedLinkAttrDeclarationBlock;
@@ -610,6 +609,7 @@ impl<'le> GeckoElement<'le> {
         }
     }
 
+    #[inline]
     fn namespace_id(&self) -> i32 {
         self.as_node().node_info().mInner.mNamespaceID
     }
@@ -658,12 +658,11 @@ impl<'le> GeckoElement<'le> {
         unsafe { Gecko_ElementState(self.0) }
     }
 
+    #[inline]
     fn document_state(&self) -> DocumentState {
-        let node = self.as_node();
-        unsafe {
-            let states = Gecko_DocumentState(node.owner_doc().0);
-            DocumentState::from_bits_truncate(states)
-        }
+        DocumentState::from_bits_truncate(
+            self.as_node().owner_doc().0.mDocumentState.mStates
+        )
     }
 
     #[inline]
@@ -1054,14 +1053,43 @@ impl<'le> TElement for GeckoElement<'le> {
     }
 
     fn get_smil_override(&self) -> Option<ArcBorrow<Locked<PropertyDeclarationBlock>>> {
-        let declarations = unsafe { Gecko_GetSMILOverrideDeclarationBlock(self.0) };
-        let declarations: Option<&RawOffsetArc<Locked<PropertyDeclarationBlock>>> =
-            declarations.and_then(|s| s.as_arc_opt());
-        declarations.map(|s| s.borrow_arc())
+        unsafe {
+            let slots = match self.get_extended_slots() {
+                Some(s) => s,
+                None => return None,
+            };
+
+            let base_declaration: &structs::DeclarationBlock =
+                match slots.mSMILOverrideStyleDeclaration.mRawPtr.as_ref() {
+                    Some(decl) => decl,
+                    None => return None,
+                };
+
+            assert_eq!(base_declaration.mType, structs::StyleBackendType_Servo);
+            let declaration: &structs::ServoDeclarationBlock =
+                mem::transmute(base_declaration);
+
+            debug_assert_eq!(
+                &declaration._base as *const structs::DeclarationBlock,
+                base_declaration as *const structs::DeclarationBlock
+            );
+
+            let raw: &structs::RawServoDeclarationBlock =
+                match declaration.mRaw.mRawPtr.as_ref() {
+                    Some(decl) => decl,
+                    None => return None,
+                };
+
+            Some(Locked::<PropertyDeclarationBlock>::as_arc(
+                &*(&raw as *const &structs::RawServoDeclarationBlock)
+            ).borrow_arc())
+        }
     }
 
-    fn get_animation_rule_by_cascade(&self, cascade_level: ServoCascadeLevel)
-                                     -> Option<Arc<Locked<PropertyDeclarationBlock>>> {
+    fn get_animation_rule_by_cascade(
+        &self,
+        cascade_level: ServoCascadeLevel,
+    ) -> Option<Arc<Locked<PropertyDeclarationBlock>>> {
         match cascade_level {
             ServoCascadeLevel::Animations => self.get_animation_rule(),
             ServoCascadeLevel::Transitions => self.get_transition_rule(),
@@ -1940,7 +1968,8 @@ impl<'le> ::selectors::Element for GeckoElement<'le> {
     #[inline]
     fn get_namespace(&self) -> &WeakNamespace {
         unsafe {
-            WeakNamespace::new(Gecko_Namespace(self.0))
+            let namespace_manager = structs::nsContentUtils_sNameSpaceManager;
+            WeakNamespace::new((*namespace_manager).mURIArray[self.namespace_id() as usize].mRawPtr)
         }
     }
 

components/style/sharing/checks.rs

@@ -12,12 +12,14 @@ use dom::TElement;
 use selectors::NthIndexCache;
 use sharing::{StyleSharingCandidate, StyleSharingTarget};
 
-/// Determines whether a target and a candidate have compatible parents for sharing.
+/// Determines whether a target and a candidate have compatible parents for
+/// sharing.
 pub fn parents_allow_sharing<E>(
     target: &mut StyleSharingTarget<E>,
     candidate: &mut StyleSharingCandidate<E>
 ) -> bool
-    where E: TElement,
+where
+    E: TElement,
 {
     // If the identity of the parent style isn't equal, we can't share. We check
     // this first, because the result is cached.
@@ -58,7 +60,8 @@ pub fn have_same_style_attribute<E>(
     target: &mut StyleSharingTarget<E>,
     candidate: &mut StyleSharingCandidate<E>
 ) -> bool
-    where E: TElement,
+where
+    E: TElement,
 {
     match (target.style_attribute(), candidate.style_attribute()) {
         (None, None) => true,
@@ -72,7 +75,8 @@ pub fn have_same_presentational_hints<E>(
     target: &mut StyleSharingTarget<E>,
     candidate: &mut StyleSharingCandidate<E>
 ) -> bool
-    where E: TElement,
+where
+    E: TElement,
 {
     target.pres_hints() == candidate.pres_hints()
 }
@@ -80,10 +84,12 @@ pub fn have_same_presentational_hints<E>(
 /// Whether a given element has the same class attribute than a given candidate.
 ///
 /// We don't try to share style across elements with different class attributes.
-pub fn have_same_class<E>(target: &mut StyleSharingTarget<E>,
-                          candidate: &mut StyleSharingCandidate<E>)
-                          -> bool
-    where E: TElement,
+pub fn have_same_class<E>(
+    target: &mut StyleSharingTarget<E>,
+    candidate: &mut StyleSharingCandidate<E>,
+) -> bool
+where
+    E: TElement,
 {
     target.class_list() == candidate.class_list()
 }