mirror of
https://github.com/Atmosphere-NX/Atmosphere.git
synced 2024-11-18 17:11:23 +00:00
93 lines
3.3 KiB
C++
93 lines
3.3 KiB
C++
/*
|
|
* Copyright (c) 2018-2020 Atmosphère-NX
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify it
|
|
* under the terms and conditions of the GNU General Public License,
|
|
* version 2, as published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope it will be useful, but WITHOUT
|
|
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
|
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
|
|
* more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#pragma once
|
|
#include <vapours/common.hpp>
|
|
#include <vapours/assert.hpp>
|
|
|
|
namespace ams::util {
|
|
|
|
namespace impl {
|
|
|
|
template<typename Storage, size_t N>
|
|
class BitSet {
|
|
private:
|
|
static_assert(std::is_integral<Storage>::value);
|
|
static_assert(std::is_unsigned<Storage>::value);
|
|
static_assert(sizeof(Storage) <= sizeof(u64));
|
|
|
|
static constexpr size_t FlagsPerWord = BITSIZEOF(Storage);
|
|
static constexpr size_t NumWords = util::AlignUp(N, FlagsPerWord) / FlagsPerWord;
|
|
|
|
static constexpr ALWAYS_INLINE auto CountLeadingZeroImpl(Storage word) {
|
|
return __builtin_clzll(static_cast<unsigned long long>(word)) - (BITSIZEOF(unsigned long long) - FlagsPerWord);
|
|
}
|
|
|
|
static constexpr ALWAYS_INLINE Storage GetBitMask(size_t bit) {
|
|
return Storage(1) << (FlagsPerWord - 1 - bit);
|
|
}
|
|
private:
|
|
Storage words[NumWords];
|
|
public:
|
|
constexpr ALWAYS_INLINE BitSet() : words() { /* ... */ }
|
|
|
|
constexpr ALWAYS_INLINE void SetBit(size_t i) {
|
|
this->words[i / FlagsPerWord] |= GetBitMask(i % FlagsPerWord);
|
|
}
|
|
|
|
constexpr ALWAYS_INLINE void ClearBit(size_t i) {
|
|
this->words[i / FlagsPerWord] &= ~GetBitMask(i % FlagsPerWord);
|
|
}
|
|
|
|
constexpr ALWAYS_INLINE size_t CountLeadingZero() const {
|
|
for (size_t i = 0; i < NumWords; i++) {
|
|
if (this->words[i]) {
|
|
return FlagsPerWord * i + CountLeadingZeroImpl(this->words[i]);
|
|
}
|
|
}
|
|
return FlagsPerWord * NumWords;
|
|
}
|
|
|
|
constexpr ALWAYS_INLINE size_t GetNextSet(size_t n) const {
|
|
for (size_t i = (n + 1) / FlagsPerWord; i < NumWords; i++) {
|
|
Storage word = this->words[i];
|
|
if (!util::IsAligned(n + 1, FlagsPerWord)) {
|
|
word &= GetBitMask(n % FlagsPerWord) - 1;
|
|
}
|
|
if (word) {
|
|
return FlagsPerWord * i + CountLeadingZeroImpl(word);
|
|
}
|
|
}
|
|
return FlagsPerWord * NumWords;
|
|
}
|
|
};
|
|
|
|
}
|
|
|
|
template<size_t N>
|
|
using BitSet8 = impl::BitSet<u8, N>;
|
|
|
|
template<size_t N>
|
|
using BitSet16 = impl::BitSet<u16, N>;
|
|
|
|
template<size_t N>
|
|
using BitSet32 = impl::BitSet<u32, N>;
|
|
|
|
template<size_t N>
|
|
using BitSet64 = impl::BitSet<u64, N>;
|
|
|
|
}
|