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Theodosius/dependencies/asmjit/core/zonehash.h

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// AsmJit - Machine code generation for C++
//
// * Official AsmJit Home Page: https://asmjit.com
// * Official Github Repository: https://github.com/asmjit/asmjit
//
// Copyright (c) 2008-2020 The AsmJit Authors
//
// This software is provided 'as-is', without any express or implied
// warranty. In no event will the authors be held liable for any damages
// arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it
// freely, subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented; you must not
// claim that you wrote the original software. If you use this software
// in a product, an acknowledgment in the product documentation would be
// appreciated but is not required.
// 2. Altered source versions must be plainly marked as such, and must not be
// misrepresented as being the original software.
// 3. This notice may not be removed or altered from any source distribution.
#ifndef ASMJIT_CORE_ZONEHASH_H_INCLUDED
#define ASMJIT_CORE_ZONEHASH_H_INCLUDED
#include "../core/zone.h"
ASMJIT_BEGIN_NAMESPACE
//! \addtogroup asmjit_zone
//! \{
// ============================================================================
// [asmjit::ZoneHashNode]
// ============================================================================
//! Node used by \ref ZoneHash template.
//!
//! You must provide function `bool eq(const Key& key)` in order to make
//! `ZoneHash::get()` working.
class ZoneHashNode {
public:
ASMJIT_NONCOPYABLE(ZoneHashNode)
inline ZoneHashNode(uint32_t hashCode = 0) noexcept
: _hashNext(nullptr),
_hashCode(hashCode),
_customData(0) {}
//! Next node in the chain, null if it terminates the chain.
ZoneHashNode* _hashNext;
//! Precalculated hash-code of key.
uint32_t _hashCode;
//! Padding, can be reused by any Node that inherits `ZoneHashNode`.
uint32_t _customData;
};
// ============================================================================
// [asmjit::ZoneHashBase]
// ============================================================================
//! Base class used by \ref ZoneHash template
class ZoneHashBase {
public:
ASMJIT_NONCOPYABLE(ZoneHashBase)
//! Buckets data.
ZoneHashNode** _data;
//! Count of records inserted into the hash table.
size_t _size;
//! Count of hash buckets.
uint32_t _bucketsCount;
//! When buckets array should grow (only checked after insertion).
uint32_t _bucketsGrow;
//! Reciprocal value of `_bucketsCount`.
uint32_t _rcpValue;
//! How many bits to shift right when hash is multiplied with `_rcpValue`.
uint8_t _rcpShift;
//! Prime value index in internal prime array.
uint8_t _primeIndex;
//! Embedded data, used by empty hash tables.
ZoneHashNode* _embedded[1];
//! \name Construction & Destruction
//! \{
inline ZoneHashBase() noexcept {
reset();
}
inline ZoneHashBase(ZoneHashBase&& other) noexcept {
_data = other._data;
_size = other._size;
_bucketsCount = other._bucketsCount;
_bucketsGrow = other._bucketsGrow;
_rcpValue = other._rcpValue;
_rcpShift = other._rcpShift;
_primeIndex = other._primeIndex;
_embedded[0] = other._embedded[0];
if (_data == other._embedded) _data = _embedded;
}
inline void reset() noexcept {
_data = _embedded;
_size = 0;
_bucketsCount = 1;
_bucketsGrow = 1;
_rcpValue = 1;
_rcpShift = 0;
_primeIndex = 0;
_embedded[0] = nullptr;
}
inline void release(ZoneAllocator* allocator) noexcept {
ZoneHashNode** oldData = _data;
if (oldData != _embedded)
allocator->release(oldData, _bucketsCount * sizeof(ZoneHashNode*));
reset();
}
//! \}
//! \name Accessors
//! \{
inline bool empty() const noexcept { return _size == 0; }
inline size_t size() const noexcept { return _size; }
//! \}
//! \name Utilities
//! \{
inline void _swap(ZoneHashBase& other) noexcept {
std::swap(_data, other._data);
std::swap(_size, other._size);
std::swap(_bucketsCount, other._bucketsCount);
std::swap(_bucketsGrow, other._bucketsGrow);
std::swap(_rcpValue, other._rcpValue);
std::swap(_rcpShift, other._rcpShift);
std::swap(_primeIndex, other._primeIndex);
std::swap(_embedded[0], other._embedded[0]);
if (_data == other._embedded) _data = _embedded;
if (other._data == _embedded) other._data = other._embedded;
}
//! \cond INTERNAL
inline uint32_t _calcMod(uint32_t hash) const noexcept {
uint32_t x = uint32_t((uint64_t(hash) * _rcpValue) >> _rcpShift);
return hash - x * _bucketsCount;
}
ASMJIT_API void _rehash(ZoneAllocator* allocator, uint32_t newCount) noexcept;
ASMJIT_API ZoneHashNode* _insert(ZoneAllocator* allocator, ZoneHashNode* node) noexcept;
ASMJIT_API ZoneHashNode* _remove(ZoneAllocator* allocator, ZoneHashNode* node) noexcept;
//! \endcond
//! \}
};
// ============================================================================
// [asmjit::ZoneHash]
// ============================================================================
//! Low-level hash table specialized for storing string keys and POD values.
//!
//! This hash table allows duplicates to be inserted (the API is so low
//! level that it's up to you if you allow it or not, as you should first
//! `get()` the node and then modify it or insert a new node by using `insert()`,
//! depending on the intention).
template<typename NodeT>
class ZoneHash : public ZoneHashBase {
public:
ASMJIT_NONCOPYABLE(ZoneHash<NodeT>)
typedef NodeT Node;
//! \name Construction & Destruction
//! \{
inline ZoneHash() noexcept
: ZoneHashBase() {}
inline ZoneHash(ZoneHash&& other) noexcept
: ZoneHash(other) {}
//! \}
//! \name Utilities
//! \{
inline void swap(ZoneHash& other) noexcept { ZoneHashBase::_swap(other); }
template<typename KeyT>
inline NodeT* get(const KeyT& key) const noexcept {
uint32_t hashMod = _calcMod(key.hashCode());
NodeT* node = static_cast<NodeT*>(_data[hashMod]);
while (node && !key.matches(node))
node = static_cast<NodeT*>(node->_hashNext);
return node;
}
inline NodeT* insert(ZoneAllocator* allocator, NodeT* node) noexcept { return static_cast<NodeT*>(_insert(allocator, node)); }
inline NodeT* remove(ZoneAllocator* allocator, NodeT* node) noexcept { return static_cast<NodeT*>(_remove(allocator, node)); }
//! \}
};
//! \}
ASMJIT_END_NAMESPACE
#endif // ASMJIT_CORE_ZONEHASH_H_INCLUDED