Mirrors/servo
1
0
Fork 0
mirror of https://github.com/servo/servo.git synced 2025-08-03 12:40:06 +01:00
Code Issues Projects Releases Packages Wiki Activity

Remove bitfield! macro in favour of bitflags!

Browse source
This commit is contained in:
Claes 'Letharion' Gyllensvärd 2014-11-16 14:39:16 +01:00
parent 64cc9ec688
commit 2737db3ad7
10 changed files with 146 additions and 175 deletions
Download patch file Download diff file Expand all files Collapse all files

171
components/layout/flow.rs
View file

@ -256,7 +256,7 @@ pub trait Flow: fmt::Show + ToString + Sync {
}
fn is_positioned(&self) -> bool {
self.is_relatively_positioned() || base(self).flags.is_absolutely_positioned()
self.is_relatively_positioned() || base(self).flags.contains(IS_ABSOLUTELY_POSITIONED)
}
fn is_relatively_positioned(&self) -> bool {
@ -457,86 +457,66 @@ pub trait PostorderFlowTraversal {
}
}
/// Flags used in flows, tightly packed to save space.
#[deriving(Clone, Encodable)]
pub struct FlowFlags(pub u16);
bitflags! {
#[doc = "Flags used in flows."]
flags FlowFlags: u16 {
// floated descendants flags
#[doc = "Whether this flow has descendants that float left in the same block formatting"]
#[doc = "context."]
const HAS_LEFT_FLOATED_DESCENDANTS = 0b0000_0000_0000_0001,
#[doc = "Whether this flow has descendants that float right in the same block formatting"]
#[doc = "context."]
const HAS_RIGHT_FLOATED_DESCENDANTS = 0b0000_0000_0000_0010,
#[doc = "Whether this flow is impacted by floats to the left in the same block formatting"]
#[doc = "context (i.e. its height depends on some prior flows with `float: left`)."]
const IMPACTED_BY_LEFT_FLOATS = 0b0000_0000_0000_0100,
#[doc = "Whether this flow is impacted by floats to the right in the same block"]
#[doc = "formatting context (i.e. its height depends on some prior flows with `float:"]
#[doc = "right`)."]
const IMPACTED_BY_RIGHT_FLOATS = 0b0000_0000_0000_1000,
// text align flags
#[doc = "Whether this flow contains a flow that has its own layer within the same absolute"]
#[doc = "containing block."]
const LAYERS_NEEDED_FOR_DESCENDANTS = 0b0000_0000_0001_0000,
#[doc = "Whether this flow must have its own layer. Even if this flag is not set, it might"]
#[doc = "get its own layer if it's deemed to be likely to overlap flows with their own"]
#[doc = "layer."]
const NEEDS_LAYER = 0b0000_0000_0010_0000,
#[doc = "Whether this flow is absolutely positioned. This is checked all over layout, so a"]
#[doc = "virtual call is too expensive."]
const IS_ABSOLUTELY_POSITIONED = 0b0000_0000_0100_0000,
#[doc = "Whether this flow clears to the left. This is checked all over layout, so a"]
#[doc = "virtual call is too expensive."]
const CLEARS_LEFT = 0b0000_0000_1000_0000,
#[doc = "Whether this flow clears to the right. This is checked all over layout, so a"]
#[doc = "virtual call is too expensive."]
const CLEARS_RIGHT = 0b0000_0001_0000_0000,
#[doc = "Whether this flow is left-floated. This is checked all over layout, so a"]
#[doc = "virtual call is too expensive."]
const FLOATS_LEFT = 0b0000_0010_0000_0000,
#[doc = "Whether this flow is right-floated. This is checked all over layout, so a"]
#[doc = "virtual call is too expensive."]
const FLOATS_RIGHT = 0b0000_0100_0000_0000,
#[doc = "Text alignment."]
const TEXT_ALIGN = 0b0000_1000_0000_0000,
}
}
// NB: If you update this field, you must update the the floated descendants flags.
/// The bitmask of flags that represent the `has_left_floated_descendants` and
/// `has_right_floated_descendants` fields.
///
/// NB: If you update this field, you must update the bitfields below.
static HAS_FLOATED_DESCENDANTS_BITMASK: u16 = 0b0000_0000_0000_0011;
// Whether this flow has descendants that float left in the same block formatting context.
bitfield!(FlowFlags,
has_left_floated_descendants,
set_has_left_floated_descendants,
0b0000_0000_0000_0001)
// Whether this flow has descendants that float right in the same block formatting context.
bitfield!(FlowFlags,
has_right_floated_descendants,
set_has_right_floated_descendants,
0b0000_0000_0000_0010)
// Whether this flow is impacted by floats to the left in the same block formatting context (i.e.
// its block-size depends on some prior flows with `float: left`).
bitfield!(FlowFlags,
impacted_by_left_floats,
set_impacted_by_left_floats,
0b0000_0000_0000_0100)
// Whether this flow is impacted by floats to the right in the same block formatting context (i.e.
// its block-size depends on some prior flows with `float: right`).
bitfield!(FlowFlags, impacted_by_right_floats, set_impacted_by_right_floats, 0b0000_0000_0000_1000)
static HAS_FLOATED_DESCENDANTS_BITMASK: FlowFlags = FlowFlags { bits: 0b0000_0011 };
// NB: If you update this field, you must update the the text align flags.
/// The bitmask of flags that represent the text alignment field.
///
/// NB: If you update this field, you must update the bitfields below.
static TEXT_ALIGN_BITMASK: u16 = 0b0000_0000_0011_0000;
static TEXT_ALIGN_BITMASK: FlowFlags = FlowFlags { bits: 0b0011_0000 };
/// The number of bits we must shift off to handle the text alignment field.
///
/// NB: If you update this field, you must update the bitfields below.
static TEXT_ALIGN_SHIFT: u16 = 4;
// Whether this flow contains a flow that has its own layer within the same absolute containing
// block.
bitfield!(FlowFlags,
layers_needed_for_descendants,
set_layers_needed_for_descendants,
0b0000_0000_0100_0000)
// Whether this flow must have its own layer. Even if this flag is not set, it might get its own
// layer if it's deemed to be likely to overlap flows with their own layer.
bitfield!(FlowFlags, needs_layer, set_needs_layer, 0b0000_0000_1000_0000)
// Whether this flow is absolutely positioned. This is checked all over layout, so a virtual call
// is too expensive.
bitfield!(FlowFlags, is_absolutely_positioned, set_is_absolutely_positioned, 0b0000_0001_0000_0000)
// Whether this flow is left-floated. This is checked all over layout, so a virtual call is too
// expensive.
bitfield!(FlowFlags, floats_left, set_floats_left, 0b0000_0010_0000_0000)
// Whether this flow is right-floated. This is checked all over layout, so a virtual call is too
// expensive.
bitfield!(FlowFlags, floats_right, set_floats_right, 0b0000_0100_0000_0000)
// Whether this flow clears to the left. This is checked all over layout, so a virtual call is too
// expensive.
bitfield!(FlowFlags, clears_left, set_clears_left, 0b0000_1000_0000_0000)
// Whether this flow clears to the right. This is checked all over layout, so a virtual call is too
// expensive.
bitfield!(FlowFlags, clears_right, set_clears_right, 0b0001_0000_0000_0000)
static TEXT_ALIGN_SHIFT: uint = 4;
impl FlowFlags {
/// Creates a new set of flow flags.
pub fn new() -> FlowFlags {
FlowFlags(0)
}
/// Propagates text alignment flags from an appropriate parent flow per CSS 2.1.
///
/// FIXME(#2265, pcwalton): It would be cleaner and faster to make this a derived CSS property
@ -547,40 +527,43 @@ impl FlowFlags {
#[inline]
pub fn text_align(self) -> text_align::T {
let FlowFlags(ff) = self;
FromPrimitive::from_u16((ff & TEXT_ALIGN_BITMASK) >> TEXT_ALIGN_SHIFT as uint).unwrap()
FromPrimitive::from_u16((self & TEXT_ALIGN_BITMASK).bits() >> TEXT_ALIGN_SHIFT).unwrap()
}
#[inline]
pub fn set_text_align(&mut self, value: text_align::T) {
let FlowFlags(ff) = *self;
*self = FlowFlags((ff & !TEXT_ALIGN_BITMASK) | ((value as u16) << TEXT_ALIGN_SHIFT as uint))
*self = (*self & !TEXT_ALIGN_BITMASK) | FlowFlags::from_bits(value as u16 << TEXT_ALIGN_SHIFT).unwrap();
}
#[inline]
pub fn set_text_align_override(&mut self, parent: FlowFlags) {
let FlowFlags(ff) = *self;
let FlowFlags(pff) = parent;
*self = FlowFlags(ff | (pff & TEXT_ALIGN_BITMASK))
self.insert(parent & TEXT_ALIGN_BITMASK);
}
#[inline]
pub fn union_floated_descendants_flags(&mut self, other: FlowFlags) {
let FlowFlags(my_flags) = *self;
let FlowFlags(other_flags) = other;
*self = FlowFlags(my_flags | (other_flags & HAS_FLOATED_DESCENDANTS_BITMASK))
self.insert(other & HAS_FLOATED_DESCENDANTS_BITMASK);
}
#[inline]
pub fn impacted_by_floats(&self) -> bool {
self.impacted_by_left_floats() || self.impacted_by_right_floats()
self.contains(IMPACTED_BY_LEFT_FLOATS) || self.contains(IMPACTED_BY_RIGHT_FLOATS)
}
#[inline]
pub fn set(&mut self, flags: FlowFlags, value: bool) {
if value {
self.insert(flags);
} else {
self.remove(flags);
}
}
#[inline]
pub fn float_kind(&self) -> float::T {
if self.floats_left() {
if self.contains(FLOATS_LEFT) {
float::left
} else if self.floats_right() {
} else if self.contains(FLOATS_RIGHT) {
float::right
} else {
float::none
@ -589,7 +572,7 @@ impl FlowFlags {
#[inline]
pub fn clears_floats(&self) -> bool {
self.clears_left() || self.clears_right()
self.contains(CLEARS_LEFT) || self.contains(CLEARS_RIGHT)
}
}
@ -854,29 +837,29 @@ impl Drop for BaseFlow {
impl BaseFlow {
#[inline]
pub fn new(node: Option<ThreadSafeLayoutNode>, writing_mode: WritingMode) -> BaseFlow {
let mut flags = FlowFlags::new();
let mut flags = FlowFlags::empty();
match node {
None => {}
Some(node) => {
let node_style = node.style();
match node_style.get_box().position {
position::absolute | position::fixed => {
flags.set_is_absolutely_positioned(true)
flags.insert(IS_ABSOLUTELY_POSITIONED)
}
_ => {}
}
match node_style.get_box().float {
float::none => {}
float::left => flags.set_floats_left(true),
float::right => flags.set_floats_right(true),
float::left => flags.insert(FLOATS_LEFT),
float::right => flags.insert(FLOATS_RIGHT),
}
match node_style.get_box().clear {
clear::none => {}
clear::left => flags.set_clears_left(true),
clear::right => flags.set_clears_right(true),
clear::left => flags.insert(CLEARS_LEFT),
clear::right => flags.insert(CLEARS_RIGHT),
clear::both => {
flags.set_clears_left(true);
flags.set_clears_right(true);
flags.insert(CLEARS_LEFT);
flags.insert(CLEARS_RIGHT);
}
}
}
@ -1211,7 +1194,7 @@ impl<'a> MutableFlowUtils for &'a mut Flow + 'a {
let mut gives_absolute_offsets = true;
if kid.is_block_like() {
let kid_block = kid.as_block();
if kid_block.is_fixed() || kid_block.base.flags.is_absolutely_positioned() {
if kid_block.is_fixed() || kid_block.base.flags.contains(IS_ABSOLUTELY_POSITIONED) {
// It won't contribute any offsets for descendants because it would be the
// containing block for them.
gives_absolute_offsets = false;