ericw-tools/include/vis/leafbits.hh

100 lines
3.0 KiB
C++

/* Copyright (C) 2012-2013 Kevin Shanahan
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that 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, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
See file, 'COPYING', for details.
*/
#pragma once
#include <cstdlib>
#include <cstring>
#include <common/cmdlib.hh>
class leafbits_t
{
size_t _size = 0;
std::unique_ptr<uint32_t[]> bits{};
constexpr size_t block_size() const { return (_size + mask) >> shift; }
inline std::unique_ptr<uint32_t[]> allocate() { return std::make_unique<uint32_t[]>(block_size()); }
constexpr size_t byte_size() const { return block_size() * sizeof(*bits.get()); }
public:
static constexpr size_t shift = 5;
static constexpr size_t mask = (sizeof(uint32_t) << 3) - 1UL;
leafbits_t() = default;
inline leafbits_t(size_t size) : _size(size), bits(allocate()) { }
inline leafbits_t(const leafbits_t &copy) : leafbits_t(copy._size)
{
memcpy(bits.get(), copy.bits.get(), byte_size());
}
inline leafbits_t(leafbits_t &&move) noexcept : _size(move._size), bits(std::move(move.bits)) { move._size = 0; }
inline leafbits_t &operator=(leafbits_t &&move) noexcept
{
_size = move._size;
bits = std::move(move.bits);
move._size = 0;
return *this;
}
inline leafbits_t &operator=(const leafbits_t &copy)
{
resize(copy._size);
memcpy(bits.get(), copy.bits.get(), byte_size());
return *this;
}
constexpr const size_t &size() const { return _size; }
// this clears existing bit data!
inline void resize(size_t new_size) { *this = leafbits_t(new_size); }
inline void clear() { memset(bits.get(), 0, byte_size()); }
inline uint32_t *data() { return bits.get(); }
inline const uint32_t *data() const { return bits.get(); }
inline bool operator[](const size_t &index) const { return !!(bits[index >> shift] & nth_bit(index & mask)); }
struct reference
{
std::unique_ptr<uint32_t[]> &bits;
size_t block_index;
size_t mask;
inline explicit operator bool() const { return !!(bits[block_index] & mask); }
inline reference &operator=(bool value)
{
if (value)
bits[block_index] |= mask;
else
bits[block_index] &= ~mask;
return *this;
}
};
inline reference operator[](const size_t &index) { return {bits, index >> shift, nth_bit(index & mask)}; }
};