Auto merge of #18620 - emilio:bye-unsafe-node, r=glennw

style: Remove UnsafeNode.

No longer needed since a while ago.

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components/layout/parallel.rs

@@ -17,21 +17,13 @@ use servo_config::opts;
 use smallvec::SmallVec;
 use std::mem;
 use std::sync::atomic::{AtomicIsize, Ordering};
-use style::dom::UnsafeNode;
 use traversal::{AssignBSizes, AssignISizes, BubbleISizes};
 use traversal::{PostorderFlowTraversal, PreorderFlowTraversal};
 
 /// Traversal chunk size.
 const CHUNK_SIZE: usize = 16;
 
-pub type FlowList = SmallVec<[UnsafeNode; CHUNK_SIZE]>;
-
-#[allow(dead_code)]
-fn static_assertion(node: UnsafeNode) {
-    unsafe {
-        let _: UnsafeFlow = ::std::intrinsics::transmute(node);
-    }
-}
+pub type FlowList = SmallVec<[UnsafeFlow; CHUNK_SIZE]>;
 
 /// Vtable + pointer representation of a Flow trait object.
 pub type UnsafeFlow = (usize, usize);

components/layout_thread/dom_wrapper.rs

@@ -61,7 +61,6 @@ use std::fmt;
 use std::fmt::Debug;
 use std::hash::{Hash, Hasher};
 use std::marker::PhantomData;
-use std::mem::transmute;
 use std::sync::atomic::Ordering;
 use style::CaseSensitivityExt;
 use style::applicable_declarations::ApplicableDeclarationBlock;
@@ -70,7 +69,7 @@ use style::computed_values::display;
 use style::context::SharedStyleContext;
 use style::data::ElementData;
 use style::dom::{LayoutIterator, NodeInfo, OpaqueNode};
-use style::dom::{PresentationalHintsSynthesizer, TElement, TNode, UnsafeNode};
+use style::dom::{PresentationalHintsSynthesizer, TElement, TNode};
 use style::element_state::*;
 use style::font_metrics::ServoMetricsProvider;
 use style::properties::{ComputedValues, PropertyDeclarationBlock};
@@ -162,17 +161,6 @@ impl<'ln> TNode for ServoLayoutNode<'ln> {
     type ConcreteElement = ServoLayoutElement<'ln>;
     type ConcreteChildrenIterator = ServoChildrenIterator<'ln>;
 
-    fn to_unsafe(&self) -> UnsafeNode {
-        unsafe {
-            (self.node.unsafe_get() as usize, 0)
-        }
-    }
-
-    unsafe fn from_unsafe(n: &UnsafeNode) -> Self {
-        let (node, _) = *n;
-        transmute(node)
-    }
-
     fn parent_node(&self) -> Option<Self> {
         unsafe {
             self.node.parent_node_ref().map(|node| self.new_with_this_lifetime(&node))

components/style/dom.rs

@@ -35,8 +35,6 @@ use std::ops::Deref;
 use stylist::Stylist;
 use traversal_flags::{TraversalFlags, self};
 
-pub use style_traits::UnsafeNode;
-
 /// An opaque handle to a node, which, unlike UnsafeNode, cannot be transformed
 /// back into a non-opaque representation. The only safe operation that can be
 /// performed on this node is to compare it to another opaque handle or to another
@@ -105,12 +103,6 @@ pub trait TNode : Sized + Copy + Clone + Debug + NodeInfo {
     /// syntax.
     type ConcreteChildrenIterator: Iterator<Item = Self>;
 
-    /// Convert this node in an `UnsafeNode`.
-    fn to_unsafe(&self) -> UnsafeNode;
-
-    /// Get a node back from an `UnsafeNode`.
-    unsafe fn from_unsafe(n: &UnsafeNode) -> Self;
-
     /// Get this node's parent node.
     fn parent_node(&self) -> Option<Self>;
 

components/style/gecko/wrapper.rs

@@ -20,7 +20,7 @@ use applicable_declarations::ApplicableDeclarationBlock;
 use atomic_refcell::{AtomicRefCell, AtomicRefMut};
 use context::{QuirksMode, SharedStyleContext, PostAnimationTasks, UpdateAnimationsTasks};
 use data::ElementData;
-use dom::{LayoutIterator, NodeInfo, TElement, TNode, UnsafeNode};
+use dom::{LayoutIterator, NodeInfo, TElement, TNode};
 use dom::{OpaqueNode, PresentationalHintsSynthesizer};
 use element_state::{ElementState, DocumentState, NS_DOCUMENT_STATE_WINDOW_INACTIVE};
 use error_reporting::ParseErrorReporter;
@@ -246,14 +246,6 @@ impl<'ln> TNode for GeckoNode<'ln> {
     type ConcreteElement = GeckoElement<'ln>;
     type ConcreteChildrenIterator = GeckoChildrenIterator<'ln>;
 
-    fn to_unsafe(&self) -> UnsafeNode {
-        (self.0 as *const _ as usize, 0)
-    }
-
-    unsafe fn from_unsafe(n: &UnsafeNode) -> Self {
-        GeckoNode(&*(n.0 as *mut RawGeckoNode))
-    }
-
     fn parent_node(&self) -> Option<Self> {
         unsafe { self.0.mParent.as_ref().map(GeckoNode) }
     }

components/style_traits/lib.rs

@@ -39,10 +39,6 @@ use selectors::parser::SelectorParseError;
 #[derive(Clone, Copy, Debug)]
 pub enum DevicePixel {}
 
-/// Opaque type stored in type-unsafe work queues for parallel layout.
-/// Must be transmutable to and from `TNode`.
-pub type UnsafeNode = (usize, usize);
-
 /// Represents a mobile style pinch zoom factor.
 /// TODO(gw): Once WR supports pinch zoom, use a type directly from webrender_api.
 #[derive(Clone, Copy, Debug, PartialEq)]