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Shared ptr bit sequence #201

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646190b
added SharedPtr to CompactBitSequenceBase
cherep58 Nov 12, 2025
66d0d98
removed old version of serializer
cherep58 Nov 12, 2025
87424c4
moved size_in_bits from SharedPtr to CompactBitSequenceBase
cherep58 Nov 12, 2025
356874e
fixed formatting
cherep58 Nov 12, 2025
78c6a52
optimizations
cherep58 Nov 12, 2025
650e53c
changed symbol_tables_type from SharedVector to BareBones::Vector in …
cherep58 Nov 14, 2025
509ea42
refactored SharedPtr
cherep58 Nov 14, 2025
16020a9
refactored SharedPtr
cherep58 Nov 15, 2025
e5fb5ee
refactored tests for series_data::Serializer/Deserializer
cherep58 Nov 15, 2025
bc79b82
Merge branch 'pp' into shared_ptr_bit_sequence
cherep58 Nov 17, 2025
a5437f9
Merge branch 'pp' into shared_ptr_bit_sequence
cherep58 Dec 2, 2025
5b128c4
fixed SharedPtr::reallocate bug with memory size calculation
cherep58 Dec 4, 2025
4117537
moved CompactBitSequence::size_in_bits_ into protected section
cherep58 Dec 4, 2025
b1d6616
fixed clang-tidy warning
cherep58 Dec 5, 2025
3cde15a
Merge branch 'pp' into shared_ptr_bit_sequence
cherep58 Dec 9, 2025
b35c19a
optimized memory allocations in CompactBitSequenceBase
cherep58 Dec 9, 2025
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165 changes: 93 additions & 72 deletions pp/bare_bones/bit_sequence.h
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Original file line number Diff line number Diff line change
Expand Up @@ -23,12 +23,13 @@
namespace BareBones {

struct AllocationSize {
uint32_t bits;
uint32_t bits{};

constexpr AllocationSize() = default;
explicit constexpr AllocationSize(uint32_t size_in_bytes) : bits(Bit::to_bits(size_in_bytes)) {}

PROMPP_ALWAYS_INLINE friend bool operator>(AllocationSize a, uint32_t b) noexcept { return a.bits > b; }
PROMPP_ALWAYS_INLINE friend bool operator>(uint32_t a, AllocationSize b) noexcept { return a > b.bits; }
PROMPP_ALWAYS_INLINE friend constexpr bool operator>(AllocationSize a, uint32_t b) noexcept { return a.bits > b; }
PROMPP_ALWAYS_INLINE friend constexpr bool operator>(uint32_t a, AllocationSize b) noexcept { return a > b.bits; }

[[nodiscard]] PROMPP_ALWAYS_INLINE constexpr uint32_t bytes() const noexcept { return Bit::to_bytes(bits); }
};
Expand Down Expand Up @@ -170,66 +171,60 @@ class BitSequenceReader {
uint64_t size_;
};

#pragma pack(push, 1)

template <std::array kAllocationSizesTable, uint32_t kReservedSizeBits>
requires std::is_same_v<typename decltype(kAllocationSizesTable)::value_type, AllocationSize>
class PROMPP_ATTRIBUTE_PACKED CompactBitSequenceBase {
class CompactBitSequenceBase {
public:
static_assert(std::size(kAllocationSizesTable) > 0);
static_assert(kAllocationSizesTable[0].bytes() == 0);

using SharedPtr = BareBones::SharedPtr<uint8_t, SharedPtrControlBlock, DefaultReallocator>;

CompactBitSequenceBase() = default;
CompactBitSequenceBase(const CompactBitSequenceBase& other)
: memory_(static_cast<uint8_t*>(std::malloc(other.allocated_memory()))),
size_in_bits_(other.size_in_bits_),
allocation_size_index_(other.allocation_size_index_) {
std::memcpy(memory_, other.memory_, other.allocated_memory());
PROMPP_ALWAYS_INLINE CompactBitSequenceBase(const CompactBitSequenceBase& other)
: memory_(other.stream_allocated_memory(), 0), size_in_bits_(other.size_in_bits_), allocation_size_index_(other.allocation_size_index_) {
std::memcpy(memory_.get(), other.memory_.get(), other.stream_allocated_memory());
}
PROMPP_ALWAYS_INLINE CompactBitSequenceBase(CompactBitSequenceBase&& other) noexcept
: memory_(other.memory_), size_in_bits_(other.size_in_bits_), allocation_size_index_(std::exchange(other.allocation_size_index_, 0)) {
other.memory_ = nullptr;
: memory_(std::move(other.memory_)),
size_in_bits_(std::exchange(other.size_in_bits_, 0)),
allocation_size_index_(std::exchange(other.allocation_size_index_, 0)) {
other.size_in_bits_ = 0;
}

CompactBitSequenceBase& operator=(const CompactBitSequenceBase& other) {
if (this != &other) {
std::free(memory_);
PROMPP_ALWAYS_INLINE CompactBitSequenceBase& operator=(const CompactBitSequenceBase& other) {
if (this != &other) [[likely]] {
const auto size = other.stream_allocated_memory();
memory_.reallocate(0, size);
std::memcpy(memory_.get(), other.memory_.get(), size);

memory_ = static_cast<uint8_t*>(std::malloc(other.allocated_memory()));
std::memcpy(memory_, other.memory_, other.allocated_memory());
size_in_bits_ = other.size_in_bits_;
allocation_size_index_ = other.allocation_size_index_;
}

return *this;
}

CompactBitSequenceBase& operator=(CompactBitSequenceBase&& other) noexcept {
if (this != &other) {
std::free(memory_);

memory_ = other.memory_;
other.memory_ = nullptr;

size_in_bits_ = other.size_in_bits_;
other.size_in_bits_ = 0;

PROMPP_ALWAYS_INLINE CompactBitSequenceBase& operator=(CompactBitSequenceBase&& other) noexcept {
if (this != &other) [[likely]] {
memory_ = std::move(other.memory_);
size_in_bits_ = std::exchange(other.size_in_bits_, 0);
allocation_size_index_ = std::exchange(other.allocation_size_index_, 0);
}

return *this;
}

~CompactBitSequenceBase() {
std::free(memory_);
memory_ = nullptr;
}

PROMPP_ALWAYS_INLINE bool operator==(const CompactBitSequenceBase& other) const noexcept {
return size_in_bits_ == other.size_in_bits_ && memcmp(memory_, other.memory_, size_in_bytes()) == 0;
return size_in_bits_ == other.size_in_bits_ && std::memcmp(memory_.get(), other.memory_.get(), size_in_bytes()) == 0;
}

PROMPP_ALWAYS_INLINE void clear() noexcept {
memory_.clear();
size_in_bits_ = 0;
allocation_size_index_ = 0;
std::free(memory_);
memory_ = nullptr;
}

[[nodiscard]] static consteval uint32_t reserved_size_in_bits() noexcept { return kReservedSizeBits; }
Expand All @@ -240,93 +235,120 @@ class PROMPP_ATTRIBUTE_PACKED CompactBitSequenceBase {
}

[[nodiscard]] PROMPP_ALWAYS_INLINE uint32_t size_in_bits() const noexcept { return size_in_bits_; }
[[nodiscard]] PROMPP_ALWAYS_INLINE uint32_t size_in_bytes() const noexcept { return Bit::to_ceil_bytes(size_in_bits_); }
[[nodiscard]] PROMPP_ALWAYS_INLINE uint32_t size_in_bytes() const noexcept { return Bit::to_ceil_bytes(size_in_bits()); }
[[nodiscard]] PROMPP_ALWAYS_INLINE uint32_t allocated_memory() const noexcept {
return is_read_only() ? (size_in_bytes() + Bit::to_bytes(kReservedSizeBits)) : kAllocationSizesTable[allocation_size_index_].bytes();
return stream_allocated_memory() + (memory_.get() != nullptr ? SharedPtr::kControlBlockSize : 0);
}
[[nodiscard]] PROMPP_ALWAYS_INLINE uint8_t allocation_size_index() const noexcept { return allocation_size_index_; }
[[nodiscard]] PROMPP_ALWAYS_INLINE bool is_read_only() const noexcept { return allocation_size_index_ == kNoAllocationIndex; }
[[nodiscard]] PROMPP_ALWAYS_INLINE std::span<const uint8_t> filled_bytes() const noexcept { return {memory_, Bit::to_bytes(size_in_bits_)}; }
[[nodiscard]] PROMPP_ALWAYS_INLINE std::span<const uint8_t> filled_bytes() const noexcept { return {memory_.get(), Bit::to_bytes(size_in_bits())}; }
template <class T>
[[nodiscard]] PROMPP_ALWAYS_INLINE std::span<const T> bytes() const noexcept {
return {reinterpret_cast<T*>(memory_), size_in_bytes() / sizeof(T)};
return {reinterpret_cast<T*>(memory_.get()), size_in_bytes() / sizeof(T)};
}
[[nodiscard]] PROMPP_ALWAYS_INLINE std::span<const uint8_t> bytes() const noexcept { return bytes<uint8_t>(); }
[[nodiscard]] PROMPP_ALWAYS_INLINE const uint8_t* raw_bytes() const noexcept { return memory_; }
[[nodiscard]] PROMPP_ALWAYS_INLINE uint8_t* raw_bytes() noexcept { return memory_; }
[[nodiscard]] PROMPP_ALWAYS_INLINE const uint8_t* raw_bytes() const noexcept { return memory_.get(); }
[[nodiscard]] PROMPP_ALWAYS_INLINE uint8_t* raw_bytes() noexcept { return memory_.get(); }
[[nodiscard]] PROMPP_ALWAYS_INLINE SharedPtr shared_memory() const noexcept { return memory_; }

PROMPP_ALWAYS_INLINE void shrink_to_fit() noexcept {
memory_ = static_cast<uint8_t*>(std::realloc(memory_, size_in_bytes() + Bit::to_bytes(kReservedSizeBits)));
const auto size = Bit::to_bytes(size_in_bits()) + Bit::to_bytes(kReservedSizeBits);
memory_.reallocate(size, size);
allocation_size_index_ = kNoAllocationIndex;
}

PROMPP_ALWAYS_INLINE void rewind() noexcept {
if (size_in_bits_ > 0) [[likely]] {
memset(memory_, '\0', allocated_memory());
size_in_bits_ = 0;
if (size_in_bits() == 0) [[unlikely]] {
return;
}

if (memory_.non_atomic_is_unique()) [[likely]] {
memset(memory_.get(), '\0', stream_allocated_memory());
} else {
memory_.clear();
}

size_in_bits_ = 0;
}

protected:
static constexpr uint32_t kNoAllocationIndex = std::numeric_limits<uint8_t>::max();

uint8_t* memory_{};
SharedPtr memory_;
uint32_t size_in_bits_{};
uint8_t allocation_size_index_{};

void reserve_enough_memory_if_needed() noexcept {
PROMPP_ALWAYS_INLINE void reserve_enough_memory_if_needed() noexcept {
assert(!is_read_only());

const auto old_size = kAllocationSizesTable[allocation_size_index_];
if (size_in_bits_ + kReservedSizeBits > old_size.bits) [[unlikely]] {
if (size_in_bits() + kReservedSizeBits > old_size.bits) [[unlikely]] {
++allocation_size_index_;
assert(allocation_size_index_ < std::size(kAllocationSizesTable));

auto new_size = kAllocationSizesTable[allocation_size_index_].bytes();
memory_ = reinterpret_cast<uint8_t*>(std::realloc(memory_, new_size));
std::memset(memory_ + old_size.bytes(), 0, new_size - old_size.bytes());
reallocate(old_size.bytes());
}
}

void reserve_enough_memory_if_needed(uint32_t needed_size) noexcept {
PROMPP_ALWAYS_INLINE void reserve_enough_memory_if_needed(uint32_t needed_size) noexcept {
assert(!is_read_only());

needed_size += size_in_bits_ + kReservedSizeBits;
needed_size += size_in_bits() + kReservedSizeBits;
auto new_allocation_size_index = allocation_size_index_;
while (needed_size > kAllocationSizesTable[new_allocation_size_index]) {
++new_allocation_size_index;
}

if (new_allocation_size_index > allocation_size_index_) {
if (new_allocation_size_index > allocation_size_index_) [[unlikely]] {
const auto old_size = kAllocationSizesTable[allocation_size_index_];
allocation_size_index_ = new_allocation_size_index;
assert(new_allocation_size_index < std::size(kAllocationSizesTable));

auto new_size = kAllocationSizesTable[allocation_size_index_].bytes();
memory_ = reinterpret_cast<uint8_t*>(std::realloc(memory_, new_size));
std::memset(memory_ + old_size.bytes(), 0, new_size - old_size.bytes());
reallocate(old_size.bytes());
}
}

PROMPP_ALWAYS_INLINE void reallocate(const uint32_t old_size_bytes) {
assert(allocation_size_index_ < std::size(kAllocationSizesTable));

const auto new_size = kAllocationSizesTable[allocation_size_index_].bytes();
memory_.reallocate(old_size_bytes, new_size);
std::memset(memory_.get() + old_size_bytes, 0, new_size - old_size_bytes);
}

template <class T>
[[nodiscard]] PROMPP_ALWAYS_INLINE T* unfilled_memory() const noexcept {
return reinterpret_cast<T*>(memory_ + Bit::to_bytes(size_in_bits_));
return reinterpret_cast<T*>(memory_.get() + Bit::to_bytes(size_in_bits()));
}

[[nodiscard]] PROMPP_ALWAYS_INLINE uint32_t unfilled_bits_in_byte() const noexcept { return size_in_bits_ % Bit::kByteBits; }
[[nodiscard]] PROMPP_ALWAYS_INLINE uint32_t unfilled_bits_in_byte() const noexcept { return size_in_bits() % Bit::kByteBits; }

[[nodiscard]] PROMPP_ALWAYS_INLINE uint32_t stream_allocated_memory() const noexcept {
return is_read_only() ? (size_in_bytes() + Bit::to_bytes(kReservedSizeBits)) : kAllocationSizesTable[allocation_size_index_].bytes();
}
};

template <std::array kAllocationSizesTable>
#pragma pack(pop)

template <size_t size>
consteval std::array<AllocationSize, size> prepare_allocation_sizes_table(const std::array<AllocationSize, size>& table) {
std::array<AllocationSize, size> new_table;
for (size_t i = 1; i < size; ++i) {
new_table[i] = AllocationSize(table[i].bytes() - sizeof(SharedPtrControlBlock));
}
return new_table;
}

template <const std::array kAllocationSizesTable>
requires std::is_same_v<typename decltype(kAllocationSizesTable)::value_type, AllocationSize>
class PROMPP_ATTRIBUTE_PACKED CompactBitSequence : public CompactBitSequenceBase<kAllocationSizesTable, Bit::to_bits(sizeof(uint64_t) + 1)> {
public:
[[nodiscard]] PROMPP_ALWAYS_INLINE BitSequenceReader reader() const noexcept { return {Base::memory_, size_in_bits_}; };
using Base = CompactBitSequenceBase<kAllocationSizesTable, Bit::to_bits(sizeof(uint64_t) + 1)>;
using Base::size_in_bits;

[[nodiscard]] PROMPP_ALWAYS_INLINE BitSequenceReader reader() const noexcept { return {Base::memory_.get(), size_in_bits()}; };

PROMPP_ALWAYS_INLINE void trim_lower_bytes(uint32_t bytes_count) {
assert(Bit::to_bits(bytes_count) <= Base::size_in_bits());
const size_t new_size_in_bytes = Base::size_in_bytes() - bytes_count;
memmove(Base::memory_, Base::memory_ + bytes_count, new_size_in_bytes);
memset(Base::memory_ + new_size_in_bytes, '\0', bytes_count);
memmove(Base::memory_.get(), Base::memory_.get() + bytes_count, new_size_in_bytes);
memset(Base::memory_.get() + new_size_in_bytes, '\0', bytes_count);
size_in_bits_ -= Bit::to_bits(bytes_count);
}

Expand Down Expand Up @@ -399,7 +421,7 @@ class PROMPP_ATTRIBUTE_PACKED CompactBitSequence : public CompactBitSequenceBase
uint32_t count = Bit::to_ceil_bytes(bit_count);

if (unfilled_bits_in_byte() == 0) [[unlikely]] {
std::memcpy(Base::memory_ + Base::size_in_bytes(), bytes, count);
std::memcpy(Base::memory_.get() + Base::size_in_bytes(), bytes, count);
size_in_bits_ += bit_count;
} else {
for (; count >= sizeof(uint64_t); count -= sizeof(uint64_t), bytes += sizeof(uint64_t)) {
Expand All @@ -418,11 +440,11 @@ class PROMPP_ATTRIBUTE_PACKED CompactBitSequence : public CompactBitSequenceBase

PROMPP_ALWAYS_INLINE void push_back_bytes(std::span<const uint8_t> bytes) noexcept { push_back_bytes(bytes.data(), Bit::to_bits(bytes.size())); }

private:
using Base = CompactBitSequenceBase<kAllocationSizesTable, Bit::to_bits(sizeof(uint64_t) + 1)>;
protected:
using Base::size_in_bits_;

private:
using Base::reserve_enough_memory_if_needed;
using Base::size_in_bits_;
using Base::unfilled_bits_in_byte;
using Base::unfilled_memory;
};
Expand All @@ -434,8 +456,7 @@ class BitSequence {
Memory<MemoryControlBlock, uint8_t> data_;

PROMPP_ALWAYS_INLINE void reserve_enough_memory_if_needed() noexcept {
if (size_ >= max_size_for_current_data_size_) {
[[unlikely]];
if (size_ >= max_size_for_current_data_size_) [[unlikely]] {
reserve_memory(size_);
}
}
Expand Down
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