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Diffstat (limited to 'layout/style/nsCSSPropertyIDSet.h')
-rw-r--r-- | layout/style/nsCSSPropertyIDSet.h | 298 |
1 files changed, 298 insertions, 0 deletions
diff --git a/layout/style/nsCSSPropertyIDSet.h b/layout/style/nsCSSPropertyIDSet.h new file mode 100644 index 0000000000..3f1d99cf60 --- /dev/null +++ b/layout/style/nsCSSPropertyIDSet.h @@ -0,0 +1,298 @@ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* bit vectors for sets of CSS properties */ + +#ifndef nsCSSPropertyIDSet_h__ +#define nsCSSPropertyIDSet_h__ + +#include <initializer_list> +#include <limits.h> // for CHAR_BIT +#include <ostream> + +#include "mozilla/ArrayUtils.h" +// For COMPOSITOR_ANIMATABLE_PROPERTY_LIST and +// COMPOSITOR_ANIMATABLE_PROPERTY_LIST_LENGTH +#include "mozilla/CompositorAnimatableProperties.h" +#include "nsCSSProps.h" // For operator<< for nsCSSPropertyID +#include "nsCSSPropertyID.h" + +/** + * nsCSSPropertyIDSet maintains a set of non-shorthand CSS properties. In + * other words, for each longhand CSS property we support, it has a bit + * for whether that property is in the set. + */ +class nsCSSPropertyIDSet { + public: + nsCSSPropertyIDSet() { Empty(); } + // auto-generated copy-constructor OK + + explicit constexpr nsCSSPropertyIDSet( + std::initializer_list<nsCSSPropertyID> aProperties) + : mProperties{0} { + for (auto property : aProperties) { + size_t p = property; + mProperties[p / kBitsInChunk] |= property_set_type(1) + << (p % kBitsInChunk); + } + } + + void AssertInSetRange(nsCSSPropertyID aProperty) const { + NS_ASSERTION(0 <= aProperty && aProperty < eCSSProperty_COUNT_no_shorthands, + "out of bounds"); + } + + // Conversion of aProperty to |size_t| after AssertInSetRange + // lets the compiler generate significantly tighter code. + + void AddProperty(nsCSSPropertyID aProperty) { + AssertInSetRange(aProperty); + size_t p = aProperty; + mProperties[p / kBitsInChunk] |= property_set_type(1) << (p % kBitsInChunk); + } + + void RemoveProperty(nsCSSPropertyID aProperty) { + AssertInSetRange(aProperty); + size_t p = aProperty; + mProperties[p / kBitsInChunk] &= + ~(property_set_type(1) << (p % kBitsInChunk)); + } + + bool HasProperty(nsCSSPropertyID aProperty) const { + AssertInSetRange(aProperty); + size_t p = aProperty; + return (mProperties[p / kBitsInChunk] & + (property_set_type(1) << (p % kBitsInChunk))) != 0; + } + + // Returns an nsCSSPropertyIDSet including all properties that can be run + // on the compositor. + static constexpr nsCSSPropertyIDSet CompositorAnimatables() { + return nsCSSPropertyIDSet(COMPOSITOR_ANIMATABLE_PROPERTY_LIST); + } + + static constexpr size_t CompositorAnimatableCount() { + return COMPOSITOR_ANIMATABLE_PROPERTY_LIST_LENGTH; + } + + static constexpr size_t CompositorAnimatableDisplayItemCount() { + // We have 3 individual transforms and 4 motion path properties, and they + // also use DisplayItemType::TYPE_TRANSFORM. + return COMPOSITOR_ANIMATABLE_PROPERTY_LIST_LENGTH - 7; + } + + static constexpr nsCSSPropertyIDSet CSSTransformProperties() { + return nsCSSPropertyIDSet{eCSSProperty_transform, eCSSProperty_translate, + eCSSProperty_rotate, eCSSProperty_scale}; + } + + static constexpr nsCSSPropertyIDSet MotionPathProperties() { + // FIXME: Bug 1559232: Add offset-position. + return nsCSSPropertyIDSet{ + eCSSProperty_offset_path, eCSSProperty_offset_distance, + eCSSProperty_offset_rotate, eCSSProperty_offset_anchor}; + } + + static constexpr nsCSSPropertyIDSet TransformLikeProperties() { + // FIXME: Bug 1559232: Add offset-position. + return nsCSSPropertyIDSet{ + eCSSProperty_transform, eCSSProperty_translate, + eCSSProperty_rotate, eCSSProperty_scale, + eCSSProperty_offset_path, eCSSProperty_offset_distance, + eCSSProperty_offset_rotate, eCSSProperty_offset_anchor}; + } + + static constexpr nsCSSPropertyIDSet OpacityProperties() { + return nsCSSPropertyIDSet{eCSSProperty_opacity}; + } + + bool Intersects(const nsCSSPropertyIDSet& aOther) const { + for (size_t i = 0; i < mozilla::ArrayLength(mProperties); ++i) { + if (mProperties[i] & aOther.mProperties[i]) { + return true; + } + } + return false; + } + + void Empty() { memset(mProperties, 0, sizeof(mProperties)); } + + void AssertIsEmpty(const char* aText) const { + for (size_t i = 0; i < mozilla::ArrayLength(mProperties); ++i) { + NS_ASSERTION(mProperties[i] == 0, aText); + } + } + + bool Equals(const nsCSSPropertyIDSet& aOther) const { + return mozilla::ArrayEqual(mProperties, aOther.mProperties); + } + + bool IsEmpty() const { + for (size_t i = 0; i < mozilla::ArrayLength(mProperties); ++i) { + if (mProperties[i] != 0) { + return false; + } + } + return true; + } + + bool IsSubsetOf(const nsCSSPropertyIDSet& aOther) const { + return this->Intersect(aOther).Equals(*this); + } + + // Return a new nsCSSPropertyIDSet which is the inverse of this set. + nsCSSPropertyIDSet Inverse() const { + nsCSSPropertyIDSet result; + for (size_t i = 0; i < mozilla::ArrayLength(mProperties); ++i) { + result.mProperties[i] = ~mProperties[i]; + } + return result; + } + + // Returns a new nsCSSPropertyIDSet with all properties that are both in + // this set and |aOther|. + nsCSSPropertyIDSet Intersect(const nsCSSPropertyIDSet& aOther) const { + nsCSSPropertyIDSet result; + for (size_t i = 0; i < mozilla::ArrayLength(mProperties); ++i) { + result.mProperties[i] = mProperties[i] & aOther.mProperties[i]; + } + return result; + } + + // Return a new nsCSSPropertyIDSet with all properties that are in either + // this set or |aOther| but not both. + nsCSSPropertyIDSet Xor(const nsCSSPropertyIDSet& aOther) const { + nsCSSPropertyIDSet result; + for (size_t i = 0; i < mozilla::ArrayLength(mProperties); ++i) { + result.mProperties[i] = mProperties[i] ^ aOther.mProperties[i]; + } + return result; + } + + nsCSSPropertyIDSet& operator|=(const nsCSSPropertyIDSet& aOther) { + for (size_t i = 0; i < mozilla::ArrayLength(mProperties); ++i) { + mProperties[i] |= aOther.mProperties[i]; + } + return *this; + } + + private: + typedef unsigned long property_set_type; + + public: + // number of bits in |property_set_type|. + static const size_t kBitsInChunk = sizeof(property_set_type) * CHAR_BIT; + // number of |property_set_type|s in the set + static const size_t kChunkCount = + (eCSSProperty_COUNT_no_shorthands + kBitsInChunk - 1) / kBitsInChunk; + + /* + * For fast enumeration of all the bits that are set, callers can + * check each chunk against zero (since in normal cases few bits are + * likely to be set). + */ + bool HasPropertyInChunk(size_t aChunk) const { + return mProperties[aChunk] != 0; + } + bool HasPropertyAt(size_t aChunk, size_t aBit) const { + return (mProperties[aChunk] & (property_set_type(1) << aBit)) != 0; + } + static nsCSSPropertyID CSSPropertyAt(size_t aChunk, size_t aBit) { + return nsCSSPropertyID(aChunk * kBitsInChunk + aBit); + } + + // Iterator for use in range-based for loops + class Iterator { + public: + Iterator(Iterator&& aOther) + : mPropertySet(aOther.mPropertySet), + mChunk(aOther.mChunk), + mBit(aOther.mBit) {} + + static Iterator BeginIterator(const nsCSSPropertyIDSet& aPropertySet) { + Iterator result(aPropertySet); + + // Search for the first property. + // Unsigned integer overflow is defined so the following is safe. + result.mBit = -1; + ++result; + + return result; + } + + static Iterator EndIterator(const nsCSSPropertyIDSet& aPropertySet) { + Iterator result(aPropertySet); + result.mChunk = kChunkCount; + result.mBit = 0; + return result; + } + + bool operator!=(const Iterator& aOther) const { + return mChunk != aOther.mChunk || mBit != aOther.mBit; + } + + Iterator& operator++() { + MOZ_ASSERT(mChunk < kChunkCount, "Should not iterate beyond end"); + + do { + mBit++; + } while (mBit < kBitsInChunk && + !mPropertySet.HasPropertyAt(mChunk, mBit)); + if (mBit != kBitsInChunk) { + return *this; + } + + do { + mChunk++; + } while (mChunk < kChunkCount && + !mPropertySet.HasPropertyInChunk(mChunk)); + mBit = 0; + if (mChunk != kChunkCount) { + while (mBit < kBitsInChunk && + !mPropertySet.HasPropertyAt(mChunk, mBit)) { + mBit++; + } + } + + return *this; + } + + nsCSSPropertyID operator*() { + MOZ_ASSERT(mChunk < kChunkCount, "Should not dereference beyond end"); + return nsCSSPropertyIDSet::CSSPropertyAt(mChunk, mBit); + } + + private: + explicit Iterator(const nsCSSPropertyIDSet& aPropertySet) + : mPropertySet(aPropertySet) {} + + Iterator() = delete; + Iterator(const Iterator&) = delete; + Iterator& operator=(const Iterator&) = delete; + Iterator& operator=(const Iterator&&) = delete; + + const nsCSSPropertyIDSet& mPropertySet; + size_t mChunk = 0; + size_t mBit = 0; + }; + + Iterator begin() const { return Iterator::BeginIterator(*this); } + Iterator end() const { return Iterator::EndIterator(*this); } + + private: + property_set_type mProperties[kChunkCount]; +}; + +// MOZ_DBG support + +inline std::ostream& operator<<(std::ostream& aOut, + const nsCSSPropertyIDSet& aPropertySet) { + AutoTArray<nsCSSPropertyID, 16> properties; + for (nsCSSPropertyID property : aPropertySet) { + properties.AppendElement(property); + } + return aOut << properties; +} + +#endif /* !defined(nsCSSPropertyIDSet_h__) */ |