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Auto merge of #7237 - servo:arc-flow, r=pcwalton

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Replace FlowRef with Arc<Flow>, now that Arc supports DST.

… and `WeakFlowRef` with `Weak<Flow>`.

r? @pcwalton

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This commit is contained in:
bors-servo 2015-08-21 15:29:35 -06:00
commit 1f9778fad9
12 changed files with 148 additions and 350 deletions
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98
components/layout/construct.rs
View file

@ -19,7 +19,7 @@ use data::{HAS_NEWLY_CONSTRUCTED_FLOW, LayoutDataWrapper};
use floats::FloatKind;
use flow::{MutableFlowUtils, MutableOwnedFlowUtils};
use flow::{self, AbsoluteDescendants, Flow, ImmutableFlowUtils, IS_ABSOLUTELY_POSITIONED};
use flow_ref::FlowRef;
use flow_ref::{self, FlowRef};
use fragment::{CanvasFragmentInfo, ImageFragmentInfo, InlineAbsoluteFragmentInfo};
use fragment::{Fragment, GeneratedContentInfo, IframeFragmentInfo};
use fragment::{InlineAbsoluteHypotheticalFragmentInfo, TableColumnFragmentInfo};
@ -375,7 +375,7 @@ impl<'a> FlowConstructor<'a> {
style,
child_node.restyle_damage(),
SpecificFragmentInfo::TableRow);
let mut new_child = FlowRef::new(box TableRowFlow::from_fragment(fragment));
let mut new_child: FlowRef = Arc::new(TableRowFlow::from_fragment(fragment));
new_child.add_new_child(child.clone());
child.finish();
*child = new_child
@ -388,7 +388,7 @@ impl<'a> FlowConstructor<'a> {
style,
child_node.restyle_damage(),
SpecificFragmentInfo::Table);
let mut new_child = FlowRef::new(box TableFlow::from_fragment(fragment));
let mut new_child: FlowRef = Arc::new(TableFlow::from_fragment(fragment));
new_child.add_new_child(child.clone());
child.finish();
*child = new_child
@ -402,7 +402,7 @@ impl<'a> FlowConstructor<'a> {
style,
child_node.restyle_damage(),
SpecificFragmentInfo::TableWrapper);
let mut new_child = FlowRef::new(box TableWrapperFlow::from_fragment(fragment, None));
let mut new_child: FlowRef = Arc::new(TableWrapperFlow::from_fragment(fragment, None));
new_child.add_new_child(child.clone());
child.finish();
*child = new_child
@ -456,9 +456,8 @@ impl<'a> FlowConstructor<'a> {
let scanned_fragments =
TextRunScanner::new().scan_for_runs(&mut self.layout_context.font_context(),
fragments.fragments);
let mut inline_flow_ref =
FlowRef::new(box InlineFlow::from_fragments(scanned_fragments,
node.style().writing_mode));
let mut inline_flow_ref: FlowRef = Arc::new(
InlineFlow::from_fragments(scanned_fragments, node.style().writing_mode));
// Add all the inline-block fragments as children of the inline flow.
for inline_block_flow in &inline_block_flows {
@ -480,7 +479,8 @@ impl<'a> FlowConstructor<'a> {
absolute_descendants.push_descendants(fragments.absolute_descendants);
{
let inline_flow = inline_flow_ref.as_mut_inline();
// FIXME(#6503): Use Arc::get_mut().unwrap() here.
let inline_flow = flow_ref::deref_mut(&mut inline_flow_ref).as_mut_inline();
let (ascent, descent) =
@ -751,12 +751,12 @@ impl<'a> FlowConstructor<'a> {
fn build_flow_for_block(&mut self, node: &ThreadSafeLayoutNode, float_kind: Option<FloatKind>)
-> ConstructionResult {
let fragment = self.build_fragment_for_block(node);
let flow = if node.style().is_multicol() {
box MulticolFlow::from_fragment(fragment, float_kind) as Box<Flow>
let flow: FlowRef = if node.style().is_multicol() {
Arc::new(MulticolFlow::from_fragment(fragment, float_kind))
} else {
box BlockFlow::from_fragment(fragment, float_kind) as Box<Flow>
Arc::new(BlockFlow::from_fragment(fragment, float_kind))
};
self.build_flow_for_block_like(FlowRef::new(flow), node)
self.build_flow_for_block_like(flow, node)
}
/// Bubbles up {ib} splits.
@ -1070,13 +1070,11 @@ impl<'a> FlowConstructor<'a> {
fn build_flow_for_table_wrapper(&mut self, node: &ThreadSafeLayoutNode, float_value: float::T)
-> ConstructionResult {
let fragment = Fragment::new(node, SpecificFragmentInfo::TableWrapper);
let wrapper_flow =
box TableWrapperFlow::from_fragment(fragment, FloatKind::from_property(float_value));
let mut wrapper_flow = FlowRef::new(wrapper_flow as Box<Flow>);
let mut wrapper_flow: FlowRef = Arc::new(
TableWrapperFlow::from_fragment(fragment, FloatKind::from_property(float_value)));
let table_fragment = Fragment::new(node, SpecificFragmentInfo::Table);
let table_flow = box TableFlow::from_fragment(table_fragment);
let table_flow = FlowRef::new(table_flow as Box<Flow>);
let table_flow = Arc::new(TableFlow::from_fragment(table_fragment));
// First populate the table flow with its children.
let construction_result = self.build_flow_for_block_like(table_flow, node);
@ -1133,8 +1131,8 @@ impl<'a> FlowConstructor<'a> {
/// with possibly other `BlockFlow`s or `InlineFlow`s underneath it.
fn build_flow_for_table_caption(&mut self, node: &ThreadSafeLayoutNode) -> ConstructionResult {
let fragment = self.build_fragment_for_block(node);
let flow = box TableCaptionFlow::from_fragment(fragment) as Box<Flow>;
self.build_flow_for_block_like(FlowRef::new(flow), node)
let flow = Arc::new(TableCaptionFlow::from_fragment(fragment));
self.build_flow_for_block_like(flow, node)
}
/// Builds a flow for a node with `display: table-row-group`. This yields a `TableRowGroupFlow`
@ -1142,16 +1140,16 @@ impl<'a> FlowConstructor<'a> {
fn build_flow_for_table_rowgroup(&mut self, node: &ThreadSafeLayoutNode)
-> ConstructionResult {
let fragment = Fragment::new(node, SpecificFragmentInfo::TableRow);
let flow = box TableRowGroupFlow::from_fragment(fragment) as Box<Flow>;
self.build_flow_for_block_like(FlowRef::new(flow), node)
let flow = Arc::new(TableRowGroupFlow::from_fragment(fragment));
self.build_flow_for_block_like(flow, node)
}
/// Builds a flow for a node with `display: table-row`. This yields a `TableRowFlow` with
/// possibly other `TableCellFlow`s underneath it.
fn build_flow_for_table_row(&mut self, node: &ThreadSafeLayoutNode) -> ConstructionResult {
let fragment = Fragment::new(node, SpecificFragmentInfo::TableRow);
let flow = box TableRowFlow::from_fragment(fragment) as Box<Flow>;
self.build_flow_for_block_like(FlowRef::new(flow), node)
let flow = Arc::new(TableRowFlow::from_fragment(fragment));
self.build_flow_for_block_like(flow, node)
}
/// Builds a flow for a node with `display: table-cell`. This yields a `TableCellFlow` with
@ -1170,9 +1168,9 @@ impl<'a> FlowConstructor<'a> {
position == position::T::fixed
});
let flow = box TableCellFlow::from_node_fragment_and_visibility_flag(node, fragment, !hide)
as Box<Flow>;
self.build_flow_for_block_like(FlowRef::new(flow), node)
let flow = Arc::new(
TableCellFlow::from_node_fragment_and_visibility_flag(node, fragment, !hide));
self.build_flow_for_block_like(flow, node)
}
/// Builds a flow for a node with `display: list-item`. This yields a `ListItemFlow` with
@ -1220,21 +1218,19 @@ impl<'a> FlowConstructor<'a> {
let main_fragment = self.build_fragment_for_block(node);
let flow = match node.style().get_list().list_style_position {
list_style_position::T::outside => {
box ListItemFlow::from_fragments_and_flotation(main_fragment,
marker_fragments,
flotation)
Arc::new(ListItemFlow::from_fragments_and_flotation(
main_fragment, marker_fragments, flotation))
}
list_style_position::T::inside => {
for marker_fragment in marker_fragments {
initial_fragments.fragments.push_back(marker_fragment)
}
box ListItemFlow::from_fragments_and_flotation(main_fragment, vec![], flotation)
Arc::new(ListItemFlow::from_fragments_and_flotation(
main_fragment, vec![], flotation))
}
};
self.build_flow_for_block_starting_with_fragments(FlowRef::new(flow as Box<Flow>),
node,
initial_fragments)
self.build_flow_for_block_starting_with_fragments(flow, node, initial_fragments)
}
/// Creates a fragment for a node with `display: table-column`.
@ -1275,8 +1271,7 @@ impl<'a> FlowConstructor<'a> {
let specific = SpecificFragmentInfo::TableColumn(TableColumnFragmentInfo::new(node));
col_fragments.push(Fragment::new(node, specific));
}
let flow = box TableColGroupFlow::from_fragments(fragment, col_fragments);
let mut flow = FlowRef::new(flow as Box<Flow>);
let mut flow: FlowRef = Arc::new(TableColGroupFlow::from_fragments(fragment, col_fragments));
flow.finish();
ConstructionResult::Flow(flow, AbsoluteDescendants::new())
@ -1317,7 +1312,8 @@ impl<'a> FlowConstructor<'a> {
if !flow.is_block_flow() {
return false
}
flow::mut_base(&mut **flow).restyle_damage.insert(damage);
let flow = flow_ref::deref_mut(flow);
flow::mut_base(flow).restyle_damage.insert(damage);
flow.repair_style_and_bubble_inline_sizes(&style);
true
}
@ -1341,27 +1337,25 @@ impl<'a> FlowConstructor<'a> {
match fragment.specific {
SpecificFragmentInfo::InlineBlock(ref mut inline_block_fragment) => {
flow::mut_base(&mut *inline_block_fragment.flow_ref).restyle_damage
.insert(damage);
let flow_ref = flow_ref::deref_mut(&mut inline_block_fragment.flow_ref);
flow::mut_base(flow_ref).restyle_damage.insert(damage);
// FIXME(pcwalton): Fragment restyle damage too?
inline_block_fragment.flow_ref
.repair_style_and_bubble_inline_sizes(&style);
flow_ref.repair_style_and_bubble_inline_sizes(&style);
}
SpecificFragmentInfo::InlineAbsoluteHypothetical(
ref mut inline_absolute_hypothetical_fragment) => {
flow::mut_base(&mut *inline_absolute_hypothetical_fragment.flow_ref)
.restyle_damage.insert(damage);
let flow_ref = flow_ref::deref_mut(
&mut inline_absolute_hypothetical_fragment.flow_ref);
flow::mut_base(flow_ref).restyle_damage.insert(damage);
// FIXME(pcwalton): Fragment restyle damage too?
inline_absolute_hypothetical_fragment
.flow_ref
.repair_style_and_bubble_inline_sizes(&style);
flow_ref.repair_style_and_bubble_inline_sizes(&style);
}
SpecificFragmentInfo::InlineAbsolute(ref mut inline_absolute_fragment) => {
flow::mut_base(&mut *inline_absolute_fragment.flow_ref).restyle_damage
.insert(damage);
let flow_ref = flow_ref::deref_mut(
&mut inline_absolute_fragment.flow_ref);
flow::mut_base(flow_ref).restyle_damage.insert(damage);
// FIXME(pcwalton): Fragment restyle damage too?
inline_absolute_fragment.flow_ref
.repair_style_and_bubble_inline_sizes(&style);
flow_ref.repair_style_and_bubble_inline_sizes(&style);
}
SpecificFragmentInfo::ScannedText(_) |
SpecificFragmentInfo::UnscannedText(_) => {
@ -1657,11 +1651,11 @@ impl FlowConstructionUtils for FlowRef {
/// This must not be public because only the layout constructor can do this.
fn add_new_child(&mut self, mut new_child: FlowRef) {
{
let kid_base = flow::mut_base(&mut *new_child);
let kid_base = flow::mut_base(flow_ref::deref_mut(&mut new_child));
kid_base.parallel.parent = parallel::mut_owned_flow_to_unsafe_flow(self);
}
let base = flow::mut_base(&mut **self);
let base = flow::mut_base(flow_ref::deref_mut(self));
base.children.push_back(new_child);
let _ = base.parallel.children_count.fetch_add(1, Ordering::Relaxed);
}
@ -1676,7 +1670,7 @@ impl FlowConstructionUtils for FlowRef {
/// This must not be public because only the layout constructor can do this.
fn finish(&mut self) {
if !opts::get().bubble_inline_sizes_separately {
self.bubble_inline_sizes()
flow_ref::deref_mut(self).bubble_inline_sizes()
}
}
}

7
components/layout/display_list_builder.rs
View file

@ -14,6 +14,7 @@ use azure::azure_hl::Color;
use block::BlockFlow;
use context::LayoutContext;
use flow::{self, BaseFlow, Flow, IS_ABSOLUTELY_POSITIONED, NEEDS_LAYER};
use flow_ref;
use fragment::{CoordinateSystem, Fragment, IframeFragmentInfo, ImageFragmentInfo};
use fragment::{ScannedTextFragmentInfo, SpecificFragmentInfo};
use inline::InlineFlow;
@ -1796,17 +1797,17 @@ impl InlineFlowDisplayListBuilding for InlineFlow {
match fragment.specific {
SpecificFragmentInfo::InlineBlock(ref mut block_flow) => {
let block_flow = &mut *block_flow.flow_ref;
let block_flow = flow_ref::deref_mut(&mut block_flow.flow_ref);
flow::mut_base(block_flow).display_list_building_result
.add_to(&mut *display_list)
}
SpecificFragmentInfo::InlineAbsoluteHypothetical(ref mut block_flow) => {
let block_flow = &mut *block_flow.flow_ref;
let block_flow = flow_ref::deref_mut(&mut block_flow.flow_ref);
flow::mut_base(block_flow).display_list_building_result
.add_to(&mut *display_list)
}
SpecificFragmentInfo::InlineAbsolute(ref mut block_flow) => {
let block_flow = &mut *block_flow.flow_ref;
let block_flow = flow_ref::deref_mut(&mut block_flow.flow_ref);
flow::mut_base(block_flow).display_list_building_result
.add_to(&mut *display_list)
}

56
components/layout/flow.rs
View file

@ -30,7 +30,7 @@ use context::LayoutContext;
use display_list_builder::DisplayListBuildingResult;
use floats::Floats;
use flow_list::{FlowList, FlowListIterator, MutFlowListIterator};
use flow_ref::{FlowRef, WeakFlowRef};
use flow_ref::{self, FlowRef, WeakFlowRef};
use fragment::{Fragment, FragmentBorderBoxIterator, SpecificFragmentInfo};
use incremental::{self, RECONSTRUCT_FLOW, REFLOW, REFLOW_OUT_OF_FLOW, RestyleDamage};
use inline::InlineFlow;
@ -57,7 +57,7 @@ use std::mem;
use std::raw;
use std::slice::IterMut;
use std::sync::Arc;
use std::sync::atomic::{AtomicUsize, Ordering};
use std::sync::atomic::Ordering;
use style::computed_values::{clear, display, empty_cells, float, position, text_align};
use style::properties::{self, ComputedValues};
use style::values::computed::LengthOrPercentageOrAuto;
@ -68,7 +68,7 @@ use util::logical_geometry::{LogicalRect, LogicalSize, WritingMode};
///
/// Note that virtual methods have a cost; we should not overuse them in Servo. Consider adding
/// methods to `ImmutableFlowUtils` or `MutableFlowUtils` before adding more methods here.
pub trait Flow: fmt::Debug + Sync {
pub trait Flow: fmt::Debug + Sync + Send + 'static {
// RTTI
//
// TODO(pcwalton): Use Rust's RTTI, once that works.
@ -770,9 +770,9 @@ pub struct AbsoluteDescendantIter<'a> {
}
impl<'a> Iterator for AbsoluteDescendantIter<'a> {
type Item = &'a mut (Flow + 'a);
fn next(&mut self) -> Option<&'a mut (Flow + 'a)> {
self.iter.next().map(|info| &mut *info.flow)
type Item = &'a mut Flow;
fn next(&mut self) -> Option<&'a mut Flow> {
self.iter.next().map(|info| flow_ref::deref_mut(&mut info.flow))
}
}
@ -814,13 +814,6 @@ impl AbsolutePositionInfo {
/// Data common to all flows.
pub struct BaseFlow {
/// NB: Must be the first element.
///
/// The necessity of this will disappear once we have dynamically-sized types.
strong_ref_count: AtomicUsize,
weak_ref_count: AtomicUsize,
pub restyle_damage: RestyleDamage,
/// The children of this flow.
@ -962,15 +955,6 @@ impl Encodable for BaseFlow {
}
}
impl Drop for BaseFlow {
fn drop(&mut self) {
if self.strong_ref_count.load(Ordering::SeqCst) != 0 &&
self.weak_ref_count.load(Ordering::SeqCst) != 0 {
panic!("Flow destroyed before its ref count hit zero—this is unsafe!")
}
}
}
/// Whether a base flow should be forced to be nonfloated. This can affect e.g. `TableFlow`, which
/// is never floated because the table wrapper flow is the floated one.
#[derive(Clone, PartialEq)]
@ -1038,8 +1022,6 @@ impl BaseFlow {
damage.remove(RECONSTRUCT_FLOW);
BaseFlow {
strong_ref_count: AtomicUsize::new(1),
weak_ref_count: AtomicUsize::new(1),
restyle_damage: damage,
children: FlowList::new(),
intrinsic_inline_sizes: IntrinsicISizes::new(),
@ -1068,16 +1050,6 @@ impl BaseFlow {
self.children.iter_mut()
}
#[allow(unsafe_code)]
pub unsafe fn strong_ref_count<'a>(&'a self) -> &'a AtomicUsize {
&self.strong_ref_count
}
#[allow(unsafe_code)]
pub unsafe fn weak_ref_count<'a>(&'a self) -> &'a AtomicUsize {
&self.weak_ref_count
}
pub fn debug_id(&self) -> usize {
let p = self as *const _;
p as usize
@ -1114,7 +1086,7 @@ impl BaseFlow {
}
}
impl<'a> ImmutableFlowUtils for &'a (Flow + 'a) {
impl<'a> ImmutableFlowUtils for &'a Flow {
/// Returns true if this flow is a block flow or subclass thereof.
fn is_block_like(self) -> bool {
match self.class() {
@ -1212,7 +1184,7 @@ impl<'a> ImmutableFlowUtils for &'a (Flow + 'a) {
/// as it's harder to understand.
fn generate_missing_child_flow(self, node: &ThreadSafeLayoutNode) -> FlowRef {
let mut style = node.style().clone();
let flow = match self.class() {
match self.class() {
FlowClass::Table | FlowClass::TableRowGroup => {
properties::modify_style_for_anonymous_table_object(
&mut style,
@ -1223,7 +1195,7 @@ impl<'a> ImmutableFlowUtils for &'a (Flow + 'a) {
style,
node.restyle_damage(),
SpecificFragmentInfo::TableRow);
box TableRowFlow::from_fragment(fragment) as Box<Flow>
Arc::new(TableRowFlow::from_fragment(fragment))
},
FlowClass::TableRow => {
properties::modify_style_for_anonymous_table_object(
@ -1236,14 +1208,12 @@ impl<'a> ImmutableFlowUtils for &'a (Flow + 'a) {
node.restyle_damage(),
SpecificFragmentInfo::TableCell);
let hide = node.style().get_inheritedtable().empty_cells == empty_cells::T::hide;
box TableCellFlow::from_node_fragment_and_visibility_flag(node, fragment, !hide) as
Box<Flow>
Arc::new(TableCellFlow::from_node_fragment_and_visibility_flag(node, fragment, !hide))
},
_ => {
panic!("no need to generate a missing child")
}
};
FlowRef::new(flow)
}
}
/// Returns true if this flow contains fragments that are roots of an absolute flow tree.
@ -1314,7 +1284,7 @@ impl<'a> ImmutableFlowUtils for &'a (Flow + 'a) {
}
}
impl<'a> MutableFlowUtils for &'a mut (Flow + 'a) {
impl<'a> MutableFlowUtils for &'a mut Flow {
/// Traverses the tree in preorder.
fn traverse_preorder<T: PreorderFlowTraversal>(self, traversal: &T) {
if traversal.should_process(self) {
@ -1384,7 +1354,7 @@ impl MutableOwnedFlowUtils for FlowRef {
/// construction is allowed to possess.
fn set_absolute_descendants(&mut self, abs_descendants: AbsoluteDescendants) {
let this = self.clone();
let base = mut_base(&mut **self);
let base = mut_base(flow_ref::deref_mut(self));
base.abs_descendants = abs_descendants;
for descendant_link in base.abs_descendants.iter() {
let descendant_base = mut_base(descendant_link);

16
components/layout/flow_list.rs
View file

@ -3,7 +3,7 @@
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
use flow::Flow;
use flow_ref::FlowRef;
use flow_ref::{self, FlowRef};
use std::collections::{linked_list, LinkedList};
@ -33,7 +33,7 @@ impl FlowList {
#[inline]
#[allow(unsafe_code)]
pub unsafe fn front_mut<'a>(&'a mut self) -> Option<&'a mut Flow> {
self.flows.front_mut().map(|head| &mut **head)
self.flows.front_mut().map(flow_ref::deref_mut)
}
/// Provide a reference to the back element, or None if the list is empty
@ -46,7 +46,7 @@ impl FlowList {
#[inline]
#[allow(unsafe_code)]
pub unsafe fn back_mut<'a>(&'a mut self) -> Option<&'a mut Flow> {
self.flows.back_mut().map(|tail| &mut **tail)
self.flows.back_mut().map(flow_ref::deref_mut)
}
/// Add an element first in the list
@ -108,9 +108,9 @@ impl FlowList {
}
impl<'a> Iterator for FlowListIterator<'a> {
type Item = &'a (Flow + 'a);
type Item = &'a Flow;
#[inline]
fn next(&mut self) -> Option<&'a (Flow + 'a)> {
fn next(&mut self) -> Option<&'a Flow> {
self.it.next().map(|x| &**x)
}
@ -121,10 +121,10 @@ impl<'a> Iterator for FlowListIterator<'a> {
}
impl<'a> Iterator for MutFlowListIterator<'a> {
type Item = &'a mut (Flow + 'a);
type Item = &'a mut Flow;
#[inline]
fn next(&mut self) -> Option<&'a mut (Flow + 'a)> {
self.it.next().map(|x| &mut **x)
fn next(&mut self) -> Option<&'a mut Flow> {
self.it.next().map(flow_ref::deref_mut)
}
#[inline]

197
components/layout/flow_ref.rs
View file

@ -8,194 +8,21 @@
//! be superfluous. This design is largely duplicating logic of Arc<T> and
//! Weak<T>; please see comments there for details.
#![allow(unsafe_code)]
use flow;
use flow::{Flow, BaseFlow};
use flow::Flow;
use std::sync::{Arc, Weak};
use std::mem;
use std::ops::{Deref, DerefMut};
use std::ptr;
use std::raw;
use std::rt::heap;
use std::sync::atomic::{self, Ordering};
pub type FlowRef = Arc<Flow>;
pub type WeakFlowRef = Weak<Flow>;
#[unsafe_no_drop_flag]
pub struct FlowRef {
object: raw::TraitObject,
}
unsafe impl Send for FlowRef {}
unsafe impl Sync for FlowRef {}
#[unsafe_no_drop_flag]
pub struct WeakFlowRef {
object: raw::TraitObject,
}
unsafe impl Send for WeakFlowRef {}
unsafe impl Sync for WeakFlowRef {}
impl FlowRef {
pub fn new(mut flow: Box<Flow>) -> FlowRef {
/// WARNING: This should only be used when there is no aliasing:
/// when the traversal ensures that no other threads accesses the same flow at the same time.
/// See https://github.com/servo/servo/issues/6503
/// Use Arc::get_mut instead when possible (e.g. on an Arc that was just created).
#[allow(unsafe_code)]
pub fn deref_mut<'a>(r: &'a mut FlowRef) -> &'a mut Flow {
let ptr: *const Flow = &**r;
unsafe {
let result = {
let flow_ref: &mut Flow = &mut *flow;
let object = mem::transmute::<&mut Flow, raw::TraitObject>(flow_ref);
FlowRef { object: object }
};
mem::forget(flow);
result
}
}
/// Downgrades the FlowRef to a WeakFlowRef.
pub fn downgrade(&self) -> WeakFlowRef {
unsafe {
flow::base(&**self).weak_ref_count().fetch_add(1, Ordering::Relaxed);
}
WeakFlowRef { object: self.object }
}
}
impl<'a> Deref for FlowRef {
type Target = Flow + 'a;
fn deref(&self) -> &(Flow + 'a) {
unsafe {
mem::transmute_copy::<raw::TraitObject, &(Flow + 'a)>(&self.object)
}
}
}
impl DerefMut for FlowRef {
fn deref_mut<'a>(&mut self) -> &mut (Flow + 'a) {
unsafe {
mem::transmute_copy::<raw::TraitObject, &mut (Flow + 'a)>(&self.object)
}
}
}
impl Drop for FlowRef {
fn drop(&mut self) {
unsafe {
if self.object.vtable.is_null() ||
self.object.vtable as usize == mem::POST_DROP_USIZE {
return
}
if flow::base(&**self).strong_ref_count().fetch_sub(1, Ordering::Release) != 1 {
return
}
atomic::fence(Ordering::Acquire);
// Normally we'd call the underlying Drop logic but not free the
// allocation, but this is almost impossible without DST in
// Rust. Instead we make a fake trait object to run the drop logic
// on.
let flow_ref: FlowRef = mem::replace(self, FlowRef {
object: raw::TraitObject {
vtable: ptr::null_mut(),
data: ptr::null_mut(),
}
});
let vtable: &[usize; 3] = mem::transmute::<*mut (), &[usize; 3]>(flow_ref.object.vtable);
let object_size = vtable[1];
let object_align = vtable[2];
let fake_data = heap::allocate(object_size, object_align);
ptr::copy(flow_ref.object.data as *const u8, fake_data, object_size);
let fake_box = raw::TraitObject { vtable: flow_ref.object.vtable, data: fake_data as *mut () };
let fake_flow = mem::transmute::<raw::TraitObject, Box<Flow>>(fake_box);
drop(fake_flow);
if flow::base(&*flow_ref).weak_ref_count().fetch_sub(1, Ordering::Release) == 1 {
atomic::fence(Ordering::Acquire);
heap::deallocate(flow_ref.object.data as *mut u8, object_size, object_align);
}
mem::forget(flow_ref);
}
}
}
impl Clone for FlowRef {
fn clone(&self) -> FlowRef {
unsafe {
let _ = flow::base(&**self).strong_ref_count().fetch_add(1, Ordering::Relaxed);
FlowRef {
object: raw::TraitObject {
vtable: self.object.vtable,
data: self.object.data,
}
}
}
}
}
fn base<'a>(r: &WeakFlowRef) -> &'a BaseFlow {
let data = r.object.data;
debug_assert!(!data.is_null());
unsafe {
mem::transmute::<*mut (), &'a BaseFlow>(data)
}
}
impl WeakFlowRef {
/// Upgrades a WeakFlowRef to a FlowRef.
pub fn upgrade(&self) -> Option<FlowRef> {
unsafe {
let object = base(self);
// We use a CAS loop to increment the strong count instead of a
// fetch_add because once the count hits 0 is must never be above
// 0.
loop {
let n = object.strong_ref_count().load(Ordering::SeqCst);
if n == 0 { return None }
let old = object.strong_ref_count().compare_and_swap(n, n + 1, Ordering::SeqCst);
if old == n {
return Some(FlowRef { object: self.object })
}
}
}
}
}
impl Clone for WeakFlowRef {
fn clone(&self) -> WeakFlowRef {
unsafe {
base(self).weak_ref_count().fetch_add(1, Ordering::Relaxed);
}
WeakFlowRef { object: self. object }
}
}
impl Drop for WeakFlowRef {
fn drop(&mut self) {
unsafe {
if self.object.vtable.is_null() ||
self.object.vtable as usize == mem::POST_DROP_USIZE {
return
}
if base(self).weak_ref_count().fetch_sub(1, Ordering::Release) == 1 {
atomic::fence(Ordering::Acquire);
// This dance deallocates the Box<Flow> without running its
// drop glue. The drop glue is run when the last strong
// reference is released.
let weak_ref: WeakFlowRef = mem::replace(self, WeakFlowRef {
object: raw::TraitObject {
vtable: ptr::null_mut(),
data: ptr::null_mut(),
}
});
let vtable: &[usize; 3] = mem::transmute::<*mut (), &[usize; 3]>(weak_ref.object.vtable);
let object_size = vtable[1];
let object_align = vtable[2];
heap::deallocate(weak_ref.object.data as *mut u8, object_size, object_align);
mem::forget(weak_ref);
}
}
&mut *(ptr as *mut Flow)
}
}

26
components/layout/fragment.rs
View file

@ -11,7 +11,7 @@ use context::LayoutContext;
use floats::ClearType;
use flow;
use flow::Flow;
use flow_ref::FlowRef;
use flow_ref::{self, FlowRef};
use incremental::{self, RestyleDamage};
use inline::{InlineFragmentContext, InlineFragmentNodeInfo, InlineMetrics};
use layout_debug;
@ -1260,11 +1260,11 @@ impl Fragment {
SpecificFragmentInfo::TableRow |
SpecificFragmentInfo::TableWrapper |
SpecificFragmentInfo::InlineAbsoluteHypothetical(_) => {}
SpecificFragmentInfo::InlineBlock(ref mut info) => {
SpecificFragmentInfo::InlineBlock(ref info) => {
let block_flow = info.flow_ref.as_block();
result.union_block(&block_flow.base.intrinsic_inline_sizes)
}
SpecificFragmentInfo::InlineAbsolute(ref mut info) => {
SpecificFragmentInfo::InlineAbsolute(ref info) => {
let block_flow = info.flow_ref.as_block();
result.union_block(&block_flow.base.intrinsic_inline_sizes)
}
@ -1647,7 +1647,7 @@ impl Fragment {
match self.specific {
SpecificFragmentInfo::InlineAbsoluteHypothetical(ref mut info) => {
let block_flow = info.flow_ref.as_mut_block();
let block_flow = flow_ref::deref_mut(&mut info.flow_ref).as_mut_block();
block_flow.base.position.size.inline =
block_flow.base.intrinsic_inline_sizes.preferred_inline_size;
@ -1655,7 +1655,7 @@ impl Fragment {
self.border_box.size.inline = Au(0);
}
SpecificFragmentInfo::InlineBlock(ref mut info) => {
let block_flow = info.flow_ref.as_mut_block();
let block_flow = flow_ref::deref_mut(&mut info.flow_ref).as_mut_block();
self.border_box.size.inline =
max(block_flow.base.intrinsic_inline_sizes.minimum_inline_size,
block_flow.base.intrinsic_inline_sizes.preferred_inline_size);
@ -1663,7 +1663,7 @@ impl Fragment {
block_flow.base.block_container_writing_mode = self.style.writing_mode;
}
SpecificFragmentInfo::InlineAbsolute(ref mut info) => {
let block_flow = info.flow_ref.as_mut_block();
let block_flow = flow_ref::deref_mut(&mut info.flow_ref).as_mut_block();
self.border_box.size.inline =
max(block_flow.base.intrinsic_inline_sizes.minimum_inline_size,
block_flow.base.intrinsic_inline_sizes.preferred_inline_size);
@ -1767,18 +1767,18 @@ impl Fragment {
}
SpecificFragmentInfo::InlineBlock(ref mut info) => {
// Not the primary fragment, so we do not take the noncontent size into account.
let block_flow = info.flow_ref.as_block();
let block_flow = flow_ref::deref_mut(&mut info.flow_ref).as_block();
self.border_box.size.block = block_flow.base.position.size.block +
block_flow.fragment.margin.block_start_end()
}
SpecificFragmentInfo::InlineAbsoluteHypothetical(ref mut info) => {
// Not the primary fragment, so we do not take the noncontent size into account.
let block_flow = info.flow_ref.as_block();
let block_flow = flow_ref::deref_mut(&mut info.flow_ref).as_block();
self.border_box.size.block = block_flow.base.position.size.block;
}
SpecificFragmentInfo::InlineAbsolute(ref mut info) => {
// Not the primary fragment, so we do not take the noncontent size into account.
let block_flow = info.flow_ref.as_block();
let block_flow = flow_ref::deref_mut(&mut info.flow_ref).as_block();
self.border_box.size.block = block_flow.base.position.size.block +
block_flow.fragment.margin.block_start_end()
}
@ -1906,7 +1906,7 @@ impl Fragment {
/// block size assignment.
pub fn update_late_computed_replaced_inline_size_if_necessary(&mut self) {
if let SpecificFragmentInfo::InlineBlock(ref mut inline_block_info) = self.specific {
let block_flow = inline_block_info.flow_ref.as_block();
let block_flow = flow_ref::deref_mut(&mut inline_block_info.flow_ref).as_block();
let margin = block_flow.fragment.style.logical_margin();
self.border_box.size.inline = block_flow.fragment.border_box.size.inline +
MaybeAuto::from_style(margin.inline_start, Au(0)).specified_or_zero() +
@ -1918,7 +1918,8 @@ impl Fragment {
match self.specific {
SpecificFragmentInfo::InlineAbsoluteHypothetical(ref mut info) => {
let position = self.border_box.start.i;
info.flow_ref.update_late_computed_inline_position_if_necessary(position)
flow_ref::deref_mut(&mut info.flow_ref)
.update_late_computed_inline_position_if_necessary(position)
}
_ => {}
}
@ -1928,7 +1929,8 @@ impl Fragment {
match self.specific {
SpecificFragmentInfo::InlineAbsoluteHypothetical(ref mut info) => {
let position = self.border_box.start.b;
info.flow_ref.update_late_computed_block_position_if_necessary(position)
flow_ref::deref_mut(&mut info.flow_ref)
.update_late_computed_block_position_if_necessary(position)
}
_ => {}
}

2
components/layout/incremental.rs
View file

@ -192,7 +192,7 @@ pub trait LayoutDamageComputation {
fn reflow_entire_document(self);
}
impl<'a> LayoutDamageComputation for &'a mut (Flow + 'a) {
impl<'a> LayoutDamageComputation for &'a mut Flow {
fn compute_layout_damage(self) -> SpecialRestyleDamage {
let mut special_damage = SpecialRestyleDamage::empty();
let is_absolutely_positioned = flow::base(self).flags.contains(IS_ABSOLUTELY_POSITIONED);

17
components/layout/inline.rs
View file

@ -10,6 +10,7 @@ use display_list_builder::{FragmentDisplayListBuilding, InlineFlowDisplayListBui
use floats::{FloatKind, Floats, PlacementInfo};
use flow::{MutableFlowUtils, OpaqueFlow};
use flow::{self, BaseFlow, FlowClass, Flow, ForceNonfloatedFlag, IS_ABSOLUTELY_POSITIONED};
use flow_ref;
use fragment::{CoordinateSystem, Fragment, FragmentBorderBoxIterator, SpecificFragmentInfo};
use incremental::{REFLOW, REFLOW_OUT_OF_FLOW, RESOLVE_GENERATED_CONTENT};
use layout_debug;
@ -1656,9 +1657,10 @@ impl Flow for InlineFlow {
let is_positioned = fragment.is_positioned();
match fragment.specific {
SpecificFragmentInfo::InlineBlock(ref mut info) => {
flow::mut_base(&mut *info.flow_ref).clip = clip;
let flow = flow_ref::deref_mut(&mut info.flow_ref);
flow::mut_base(flow).clip = clip;
let block_flow = info.flow_ref.as_mut_block();
let block_flow = flow.as_mut_block();
block_flow.base.absolute_position_info = self.base.absolute_position_info;
let stacking_relative_position = self.base.stacking_relative_position;
@ -1676,9 +1678,9 @@ impl Flow for InlineFlow {
self.base.stacking_relative_position_of_display_port;
}
SpecificFragmentInfo::InlineAbsoluteHypothetical(ref mut info) => {
flow::mut_base(&mut *info.flow_ref).clip = clip;
let block_flow = info.flow_ref.as_mut_block();
let flow = flow_ref::deref_mut(&mut info.flow_ref);
flow::mut_base(flow).clip = clip;
let block_flow = flow.as_mut_block();
block_flow.base.absolute_position_info = self.base.absolute_position_info;
block_flow.base.stacking_relative_position =
@ -1687,9 +1689,10 @@ impl Flow for InlineFlow {
self.base.stacking_relative_position_of_display_port;
}
SpecificFragmentInfo::InlineAbsolute(ref mut info) => {
flow::mut_base(&mut *info.flow_ref).clip = clip;
let flow = flow_ref::deref_mut(&mut info.flow_ref);
flow::mut_base(flow).clip = clip;
let block_flow = info.flow_ref.as_mut_block();
let block_flow = flow.as_mut_block();
block_flow.base.absolute_position_info = self.base.absolute_position_info;
let stacking_relative_position = self.base.stacking_relative_position;

22
components/layout/layout_task.rs
View file

@ -14,7 +14,7 @@ use cssparser::ToCss;
use data::LayoutDataWrapper;
use display_list_builder::ToGfxColor;
use flow::{self, Flow, ImmutableFlowUtils, MutableFlowUtils, MutableOwnedFlowUtils};
use flow_ref::FlowRef;
use flow_ref::{self, FlowRef};
use fragment::{Fragment, FragmentBorderBoxIterator, SpecificFragmentInfo};
use incremental::{LayoutDamageComputation, REFLOW, REFLOW_ENTIRE_DOCUMENT, REPAINT};
use layout_debug;
@ -781,7 +781,7 @@ impl LayoutTask {
_ => return None,
};
flow.mark_as_root();
flow_ref::deref_mut(&mut flow).mark_as_root();
Some(flow)
}
@ -999,11 +999,11 @@ impl LayoutTask {
self.profiler_metadata(),
self.time_profiler_chan.clone(),
|| {
flow::mut_base(&mut **layout_root).stacking_relative_position =
flow::mut_base(flow_ref::deref_mut(layout_root)).stacking_relative_position =
LogicalPoint::zero(writing_mode).to_physical(writing_mode,
rw_data.screen_size);
flow::mut_base(&mut **layout_root).clip =
flow::mut_base(flow_ref::deref_mut(layout_root)).clip =
ClippingRegion::from_rect(&data.page_clip_rect);
match (&mut rw_data.parallel_traversal, opts::get().parallel_display_list_building) {
@ -1023,13 +1023,15 @@ impl LayoutTask {
if data.goal == ReflowGoal::ForDisplay {
debug!("Done building display list.");
let root_background_color = get_root_flow_background_color(&mut **layout_root);
let root_background_color = get_root_flow_background_color(
flow_ref::deref_mut(layout_root));
let root_size = {
let root_flow = flow::base(&**layout_root);
root_flow.position.size.to_physical(root_flow.writing_mode)
};
let mut display_list = box DisplayList::new();
flow::mut_base(&mut **layout_root).display_list_building_result
flow::mut_base(flow_ref::deref_mut(layout_root))
.display_list_building_result
.add_to(&mut *display_list);
let paint_layer = PaintLayer::new(layout_root.layer_id(0),
root_background_color,
@ -1128,7 +1130,7 @@ impl LayoutTask {
}
if needs_reflow {
if let Some(mut flow) = self.try_get_layout_root(*node) {
LayoutTask::reflow_all_nodes(&mut *flow);
LayoutTask::reflow_all_nodes(flow_ref::deref_mut(&mut flow));
}
}
@ -1289,7 +1291,7 @@ impl LayoutTask {
self.profiler_metadata(),
self.time_profiler_chan.clone(),
|| {
animation::recalc_style_for_animations(root_flow.deref_mut(),
animation::recalc_style_for_animations(flow_ref::deref_mut(&mut root_flow),
animations)
});
}
@ -1309,10 +1311,10 @@ impl LayoutTask {
self.profiler_metadata(),
self.time_profiler_chan.clone(),
|| {
if opts::get().nonincremental_layout || root_flow.deref_mut()
if opts::get().nonincremental_layout || flow_ref::deref_mut(&mut root_flow)
.compute_layout_damage()
.contains(REFLOW_ENTIRE_DOCUMENT) {
root_flow.deref_mut().reflow_entire_document()
flow_ref::deref_mut(&mut root_flow).reflow_entire_document()
}
});

3
components/layout/lib.rs
View file

@ -4,13 +4,12 @@
#![feature(append)]
#![feature(arc_unique)]
#![feature(arc_weak)]
#![feature(box_str)]
#![feature(box_syntax)]
#![feature(cell_extras)]
#![feature(custom_derive)]
#![feature(filling_drop)]
#![feature(hashmap_hasher)]
#![feature(heap_api)]
#![feature(mpsc_select)]
#![feature(plugin)]
#![feature(raw)]

42
components/layout/parallel.rs
View file

@ -11,7 +11,7 @@
use context::{LayoutContext, SharedLayoutContext};
use flow;
use flow::{Flow, MutableFlowUtils, PreorderFlowTraversal, PostorderFlowTraversal};
use flow_ref::FlowRef;
use flow_ref::{self, FlowRef};
use traversal::PostorderNodeMutTraversal;
use traversal::{BubbleISizes, AssignISizes, AssignBSizesAndStoreOverflow};
use traversal::{ComputeAbsolutePositions, BuildDisplayList};
@ -47,25 +47,25 @@ fn null_unsafe_flow() -> UnsafeFlow {
pub fn owned_flow_to_unsafe_flow(flow: *const FlowRef) -> UnsafeFlow {
unsafe {
mem::transmute_copy(&*flow)
mem::transmute::<&Flow, UnsafeFlow>(&**flow)
}
}
pub fn mut_owned_flow_to_unsafe_flow(flow: *mut FlowRef) -> UnsafeFlow {
unsafe {
mem::transmute_copy(&*flow)
mem::transmute::<&Flow, UnsafeFlow>(&**flow)
}
}
pub fn borrowed_flow_to_unsafe_flow(flow: &Flow) -> UnsafeFlow {
unsafe {
mem::transmute_copy(&flow)
mem::transmute::<&Flow, UnsafeFlow>(flow)
}
}
pub fn mut_borrowed_flow_to_unsafe_flow(flow: &mut Flow) -> UnsafeFlow {
unsafe {
mem::transmute_copy(&flow)
mem::transmute::<&Flow, UnsafeFlow>(flow)
}
}
@ -239,24 +239,24 @@ trait ParallelPostorderFlowTraversal : PostorderFlowTraversal {
fn run_parallel(&self, mut unsafe_flow: UnsafeFlow) {
loop {
// Get a real flow.
let flow: &mut FlowRef = unsafe {
mem::transmute(&mut unsafe_flow)
let flow: &mut Flow = unsafe {
mem::transmute(unsafe_flow)
};
// Perform the appropriate traversal.
if self.should_process(&mut **flow) {
self.process(&mut **flow);
if self.should_process(flow) {
self.process(flow);
}
let base = flow::mut_base(&mut **flow);
let base = flow::mut_base(flow);
// Reset the count of children for the next layout traversal.
base.parallel.children_count.store(base.children.len() as isize,
Ordering::Relaxed);
// Possibly enqueue the parent.
let mut unsafe_parent = base.parallel.parent;
let unsafe_parent = base.parallel.parent;
if unsafe_parent == null_unsafe_flow() {
// We're done!
break
@ -265,10 +265,10 @@ trait ParallelPostorderFlowTraversal : PostorderFlowTraversal {
// No, we're not at the root yet. Then are we the last child
// of our parent to finish processing? If so, we can continue
// on with our parent; otherwise, we've gotta wait.
let parent: &mut FlowRef = unsafe {
mem::transmute(&mut unsafe_parent)
let parent: &mut Flow = unsafe {
mem::transmute(unsafe_parent)
};
let parent_base = flow::mut_base(&mut **parent);
let parent_base = flow::mut_base(parent);
if parent_base.parallel.children_count.fetch_sub(1, Ordering::Relaxed) == 1 {
// We were the last child of our parent. Reflow our parent.
unsafe_flow = unsafe_parent
@ -295,23 +295,23 @@ trait ParallelPreorderFlowTraversal : PreorderFlowTraversal {
top_down_func: ChunkedFlowTraversalFunction,
bottom_up_func: FlowTraversalFunction) {
let mut discovered_child_flows = Vec::new();
for mut unsafe_flow in *unsafe_flows.0 {
for unsafe_flow in *unsafe_flows.0 {
let mut had_children = false;
unsafe {
// Get a real flow.
let flow: &mut FlowRef = mem::transmute(&mut unsafe_flow);
let flow: &mut Flow = mem::transmute(unsafe_flow);
if self.should_record_thread_ids() {
flow::mut_base(&mut **flow).thread_id = proxy.worker_index();
flow::mut_base(flow).thread_id = proxy.worker_index();
}
if self.should_process(&mut **flow) {
if self.should_process(flow) {
// Perform the appropriate traversal.
self.process(&mut **flow);
self.process(flow);
}
// Possibly enqueue the children.
for kid in flow::child_iter(&mut **flow) {
for kid in flow::child_iter(flow) {
had_children = true;
discovered_child_flows.push(borrowed_flow_to_unsafe_flow(kid));
}
@ -470,7 +470,7 @@ pub fn traverse_flow_tree_preorder(
if opts::get().bubble_inline_sizes_separately {
let layout_context = LayoutContext::new(shared_layout_context);
let bubble_inline_sizes = BubbleISizes { layout_context: &layout_context };
root.traverse_postorder(&bubble_inline_sizes);
flow_ref::deref_mut(root).traverse_postorder(&bubble_inline_sizes);
}
run_queue_with_custom_work_data_type(queue, |queue| {

10
components/layout/sequential.rs
View file

@ -7,7 +7,7 @@
use context::{LayoutContext, SharedLayoutContext};
use flow::{PostorderFlowTraversal, PreorderFlowTraversal};
use flow::{self, Flow, ImmutableFlowUtils, InorderFlowTraversal, MutableFlowUtils};
use flow_ref::FlowRef;
use flow_ref::{self, FlowRef};
use fragment::FragmentBorderBoxIterator;
use generated_content::ResolveGeneratedContent;
use traversal::PostorderNodeMutTraversal;
@ -55,7 +55,7 @@ pub fn resolve_generated_content(root: &mut FlowRef, shared_layout_context: &Sha
let layout_context = LayoutContext::new(shared_layout_context);
let mut traversal = ResolveGeneratedContent::new(&layout_context);
doit(&mut **root, 0, &mut traversal)
doit(flow_ref::deref_mut(root), 0, &mut traversal)
}
pub fn traverse_flow_tree_preorder(root: &mut FlowRef,
@ -78,7 +78,7 @@ pub fn traverse_flow_tree_preorder(root: &mut FlowRef,
let layout_context = LayoutContext::new(shared_layout_context);
let root = &mut **root;
let root = flow_ref::deref_mut(root);
if opts::get().bubble_inline_sizes_separately {
let bubble_inline_sizes = BubbleISizes { layout_context: &layout_context };
@ -116,7 +116,7 @@ pub fn build_display_list_for_subtree(root: &mut FlowRef,
let compute_absolute_positions = ComputeAbsolutePositions { layout_context: &layout_context };
let build_display_list = BuildDisplayList { layout_context: &layout_context };
doit(&mut **root, compute_absolute_positions, build_display_list);
doit(flow_ref::deref_mut(root), compute_absolute_positions, build_display_list);
}
pub fn iterate_through_flow_tree_fragment_border_boxes(root: &mut FlowRef,
@ -141,5 +141,5 @@ pub fn iterate_through_flow_tree_fragment_border_boxes(root: &mut FlowRef,
}
}
doit(&mut **root, 0, iterator, &ZERO_POINT);
doit(flow_ref::deref_mut(root), 0, iterator, &ZERO_POINT);
}