chromium/third_party/dawn/src/dawn/common/BitSetIterator.h

// Copyright 2017 The Dawn & Tint Authors
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#ifndef SRC_DAWN_COMMON_BITSETITERATOR_H_
#define SRC_DAWN_COMMON_BITSETITERATOR_H_

#include <bitset>
#include <limits>

#include "dawn/common/Assert.h"
#include "dawn/common/Math.h"
#include "dawn/common/UnderlyingType.h"

namespace dawn {

// This is ANGLE's BitSetIterator class with a customizable return type.
// Types have been updated to be more specific.
// TODO(crbug.com/dawn/306): it could be optimized, in particular when N <= 64

template <typename T>
T roundUp(const T value, const T alignment) { … }

template <size_t N, typename T>
class BitSetIterator final { … };

template <size_t N, typename T>
BitSetIterator<N, T>::BitSetIterator(const std::bitset<N>& bitset) : … { … }

template <size_t N, typename T>
BitSetIterator<N, T>::BitSetIterator(const BitSetIterator& other) : … { … }

template <size_t N, typename T>
BitSetIterator<N, T>& BitSetIterator<N, T>::operator=(const BitSetIterator& other) { … }

template <size_t N, typename T>
BitSetIterator<N, T>::Iterator::Iterator(const std::bitset<N>& bits)
    : … { … }

template <size_t N, typename T>
typename BitSetIterator<N, T>::Iterator& BitSetIterator<N, T>::Iterator::operator++() { … }

template <size_t N, typename T>
bool BitSetIterator<N, T>::Iterator::operator==(const Iterator& other) const { … }

template <size_t N, typename T>
bool BitSetIterator<N, T>::Iterator::operator!=(const Iterator& other) const { … }

template <size_t N, typename T>
uint32_t BitSetIterator<N, T>::Iterator::getNextBit() { … }

// Helper to avoid needing to specify the template parameter size
template <size_t N>
BitSetIterator<N, uint32_t> IterateBitSet(const std::bitset<N>& bitset) { … }

}  // namespace dawn

#endif  // SRC_DAWN_COMMON_BITSETITERATOR_H_