| /* |
| * Copyright (C) 2014, The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #ifndef LATINIME_TRIE_MAP_H |
| #define LATINIME_TRIE_MAP_H |
| |
| #include <climits> |
| #include <cstdint> |
| #include <vector> |
| |
| #include "defines.h" |
| #include "suggest/policyimpl/dictionary/utils/buffer_with_extendable_buffer.h" |
| |
| namespace latinime { |
| |
| /** |
| * Trie map derived from Phil Bagwell's Hash Array Mapped Trie. |
| * key is int and value is uint64_t. |
| * This supports multiple level map. Terminal entries can have a bitmap for the next level map. |
| * This doesn't support root map resizing. |
| */ |
| class TrieMap { |
| public: |
| struct Result { |
| const uint64_t mValue; |
| const bool mIsValid; |
| const int mNextLevelBitmapEntryIndex; |
| |
| Result(const uint64_t value, const bool isValid, const int nextLevelBitmapEntryIndex) |
| : mValue(value), mIsValid(isValid), |
| mNextLevelBitmapEntryIndex(nextLevelBitmapEntryIndex) {} |
| }; |
| |
| /** |
| * Struct to record iteration state in a table. |
| */ |
| struct TableIterationState { |
| int mTableSize; |
| int mTableIndex; |
| int mCurrentIndex; |
| |
| TableIterationState(const int tableSize, const int tableIndex) |
| : mTableSize(tableSize), mTableIndex(tableIndex), mCurrentIndex(0) {} |
| }; |
| |
| class TrieMapRange; |
| class TrieMapIterator { |
| public: |
| class IterationResult { |
| public: |
| IterationResult(const TrieMap *const trieMap, const int key, const uint64_t value, |
| const int nextLeveBitmapEntryIndex) |
| : mTrieMap(trieMap), mKey(key), mValue(value), |
| mNextLevelBitmapEntryIndex(nextLeveBitmapEntryIndex) {} |
| |
| const TrieMapRange getEntriesInNextLevel() const { |
| return TrieMapRange(mTrieMap, mNextLevelBitmapEntryIndex); |
| } |
| |
| bool hasNextLevelMap() const { |
| return mNextLevelBitmapEntryIndex != INVALID_INDEX; |
| } |
| |
| AK_FORCE_INLINE int key() const { |
| return mKey; |
| } |
| |
| AK_FORCE_INLINE uint64_t value() const { |
| return mValue; |
| } |
| |
| private: |
| const TrieMap *const mTrieMap; |
| const int mKey; |
| const uint64_t mValue; |
| const int mNextLevelBitmapEntryIndex; |
| }; |
| |
| TrieMapIterator(const TrieMap *const trieMap, const int bitmapEntryIndex) |
| : mTrieMap(trieMap), mStateStack(), mBaseBitmapEntryIndex(bitmapEntryIndex), |
| mKey(0), mValue(0), mIsValid(false), mNextLevelBitmapEntryIndex(INVALID_INDEX) { |
| if (!trieMap) { |
| return; |
| } |
| const Entry bitmapEntry = mTrieMap->readEntry(mBaseBitmapEntryIndex); |
| mStateStack.emplace_back( |
| mTrieMap->popCount(bitmapEntry.getBitmap()), bitmapEntry.getTableIndex()); |
| this->operator++(); |
| } |
| |
| const IterationResult operator*() const { |
| return IterationResult(mTrieMap, mKey, mValue, mNextLevelBitmapEntryIndex); |
| } |
| |
| bool operator!=(const TrieMapIterator &other) const { |
| // Caveat: This works only for for loops. |
| return mIsValid || other.mIsValid; |
| } |
| |
| const TrieMapIterator &operator++() { |
| const Result result = mTrieMap->iterateNext(&mStateStack, &mKey); |
| mValue = result.mValue; |
| mIsValid = result.mIsValid; |
| mNextLevelBitmapEntryIndex = result.mNextLevelBitmapEntryIndex; |
| return *this; |
| } |
| |
| private: |
| DISALLOW_DEFAULT_CONSTRUCTOR(TrieMapIterator); |
| DISALLOW_ASSIGNMENT_OPERATOR(TrieMapIterator); |
| |
| const TrieMap *const mTrieMap; |
| std::vector<TrieMap::TableIterationState> mStateStack; |
| const int mBaseBitmapEntryIndex; |
| int mKey; |
| uint64_t mValue; |
| bool mIsValid; |
| int mNextLevelBitmapEntryIndex; |
| }; |
| |
| /** |
| * Class to support iterating entries in TrieMap by range base for loops. |
| */ |
| class TrieMapRange { |
| public: |
| TrieMapRange(const TrieMap *const trieMap, const int bitmapEntryIndex) |
| : mTrieMap(trieMap), mBaseBitmapEntryIndex(bitmapEntryIndex) {}; |
| |
| TrieMapIterator begin() const { |
| return TrieMapIterator(mTrieMap, mBaseBitmapEntryIndex); |
| } |
| |
| const TrieMapIterator end() const { |
| return TrieMapIterator(nullptr, INVALID_INDEX); |
| } |
| |
| private: |
| DISALLOW_DEFAULT_CONSTRUCTOR(TrieMapRange); |
| DISALLOW_ASSIGNMENT_OPERATOR(TrieMapRange); |
| |
| const TrieMap *const mTrieMap; |
| const int mBaseBitmapEntryIndex; |
| }; |
| |
| static const int INVALID_INDEX; |
| static const uint64_t MAX_VALUE; |
| |
| TrieMap(); |
| void dump(const int from = 0, const int to = 0) const; |
| |
| bool isNearSizeLimit() const { |
| return mBuffer.isNearSizeLimit(); |
| } |
| |
| // Returns bitmapEntryIndex. Create the next level map if it doesn't exist. |
| int getNextLevelBitmapEntryIndex(const int key) { |
| return getNextLevelBitmapEntryIndex(key, ROOT_BITMAP_ENTRY_INDEX); |
| } |
| |
| int getNextLevelBitmapEntryIndex(const int key, const int bitmapEntryIndex); |
| |
| const Result getRoot(const int key) const { |
| return get(key, ROOT_BITMAP_ENTRY_INDEX); |
| } |
| |
| const Result get(const int key, const int bitmapEntryIndex) const; |
| |
| bool putRoot(const int key, const uint64_t value) { |
| return put(key, value, ROOT_BITMAP_ENTRY_INDEX); |
| } |
| |
| bool put(const int key, const uint64_t value, const int bitmapEntryIndex); |
| |
| const TrieMapRange getEntriesInRootLevel() const { |
| return getEntriesInSpecifiedLevel(ROOT_BITMAP_ENTRY_INDEX); |
| } |
| |
| const TrieMapRange getEntriesInSpecifiedLevel(const int bitmapEntryIndex) const { |
| return TrieMapRange(this, bitmapEntryIndex); |
| } |
| |
| private: |
| DISALLOW_COPY_AND_ASSIGN(TrieMap); |
| |
| /** |
| * Struct represents an entry. |
| * |
| * Entry is one of these entry types. All entries are fixed size and have 2 fields FIELD_0 and |
| * FIELD_1. |
| * 1. bitmap entry. bitmap entry contains bitmap and the link to hash table. |
| * FIELD_0(bitmap) FIELD_1(LINK_TO_HASH_TABLE) |
| * 2. terminal entry. terminal entry contains hashed key and value or terminal link. terminal |
| * entry have terminal link when the value is not fit to FIELD_1 or there is a next level map |
| * for the key. |
| * FIELD_0(hashed key) (FIELD_1(VALUE_FLAG VALUE) | FIELD_1(TERMINAL_LINK_FLAG TERMINAL_LINK)) |
| * 3. value entry. value entry represents a value. Upper order bytes are stored in FIELD_0 and |
| * lower order bytes are stored in FIELD_1. |
| * FIELD_0(value (upper order bytes)) FIELD_1(value (lower order bytes)) |
| */ |
| struct Entry { |
| const uint32_t mData0; |
| const uint32_t mData1; |
| |
| Entry(const uint32_t data0, const uint32_t data1) : mData0(data0), mData1(data1) {} |
| |
| AK_FORCE_INLINE bool isBitmapEntry() const { |
| return (mData1 & VALUE_FLAG) == 0 && (mData1 & TERMINAL_LINK_FLAG) == 0; |
| } |
| |
| AK_FORCE_INLINE bool hasTerminalLink() const { |
| return (mData1 & TERMINAL_LINK_FLAG) != 0; |
| } |
| |
| // For terminal entry. |
| AK_FORCE_INLINE uint32_t getKey() const { |
| return mData0; |
| } |
| |
| // For terminal entry. |
| AK_FORCE_INLINE uint32_t getValue() const { |
| return mData1 & VALUE_MASK; |
| } |
| |
| // For terminal entry. |
| AK_FORCE_INLINE uint32_t getValueEntryIndex() const { |
| return mData1 & TERMINAL_LINK_MASK; |
| } |
| |
| // For bitmap entry. |
| AK_FORCE_INLINE uint32_t getBitmap() const { |
| return mData0; |
| } |
| |
| // For bitmap entry. |
| AK_FORCE_INLINE int getTableIndex() const { |
| return static_cast<int>(mData1); |
| } |
| |
| // For value entry. |
| AK_FORCE_INLINE uint64_t getValueOfValueEntry() const { |
| return ((static_cast<uint64_t>(mData0) << (FIELD1_SIZE * CHAR_BIT)) ^ mData1); |
| } |
| }; |
| |
| BufferWithExtendableBuffer mBuffer; |
| |
| static const int FIELD0_SIZE; |
| static const int FIELD1_SIZE; |
| static const int ENTRY_SIZE; |
| static const uint32_t VALUE_FLAG; |
| static const uint32_t VALUE_MASK; |
| static const uint32_t TERMINAL_LINK_FLAG; |
| static const uint32_t TERMINAL_LINK_MASK; |
| static const int NUM_OF_BITS_USED_FOR_ONE_LEVEL; |
| static const uint32_t LABEL_MASK; |
| static const int MAX_NUM_OF_ENTRIES_IN_ONE_LEVEL; |
| static const int ROOT_BITMAP_ENTRY_INDEX; |
| static const int ROOT_BITMAP_ENTRY_POS; |
| static const Entry EMPTY_BITMAP_ENTRY; |
| static const int MAX_BUFFER_SIZE; |
| |
| uint32_t getBitShuffledKey(const uint32_t key) const; |
| bool writeValue(const uint64_t value, const int terminalEntryIndex); |
| bool updateValue(const Entry &terminalEntry, const uint64_t value, |
| const int terminalEntryIndex); |
| bool freeTable(const int tableIndex, const int entryCount); |
| int allocateTable(const int entryCount); |
| int getTerminalEntryIndex(const uint32_t key, const uint32_t hashedKey, |
| const Entry &bitmapEntry, const int level) const; |
| const Result getInternal(const uint32_t key, const uint32_t hashedKey, |
| const int bitmapEntryIndex, const int level) const; |
| bool putInternal(const uint32_t key, const uint64_t value, const uint32_t hashedKey, |
| const int bitmapEntryIndex, const Entry &bitmapEntry, const int level); |
| bool addNewEntryByResolvingConflict(const uint32_t key, const uint64_t value, |
| const uint32_t hashedKey, const Entry &conflictedEntry, const int conflictedEntryIndex, |
| const int level); |
| bool addNewEntryByExpandingTable(const uint32_t key, const uint64_t value, |
| const int tableIndex, const uint32_t bitmap, const int bitmapEntryIndex, |
| const int label); |
| const Result iterateNext(std::vector<TableIterationState> *const iterationState, |
| int *const outKey) const; |
| |
| AK_FORCE_INLINE const Entry readEntry(const int entryIndex) const { |
| return Entry(readField0(entryIndex), readField1(entryIndex)); |
| } |
| |
| // Returns whether an entry for the index is existing by testing if the index-th bit in the |
| // bitmap is set or not. |
| AK_FORCE_INLINE bool exists(const uint32_t bitmap, const int index) const { |
| return (bitmap & (1 << index)) != 0; |
| } |
| |
| // Set index-th bit in the bitmap. |
| AK_FORCE_INLINE uint32_t setExist(const uint32_t bitmap, const int index) const { |
| return bitmap | (1 << index); |
| } |
| |
| // Count set bits before index in the bitmap. |
| AK_FORCE_INLINE int popCount(const uint32_t bitmap, const int index) const { |
| return popCount(bitmap & ((1 << index) - 1)); |
| } |
| |
| // Count set bits in the bitmap. |
| AK_FORCE_INLINE int popCount(const uint32_t bitmap) const { |
| return __builtin_popcount(bitmap); |
| // int v = bitmap - ((bitmap >> 1) & 0x55555555); |
| // v = (v & 0x33333333) + ((v >> 2) & 0x33333333); |
| // return (((v + (v >> 4)) & 0x0F0F0F0F) * 0x01010101) >> 24; |
| } |
| |
| AK_FORCE_INLINE int getLabel(const uint32_t hashedKey, const int level) const { |
| return (hashedKey >> (level * NUM_OF_BITS_USED_FOR_ONE_LEVEL)) & LABEL_MASK; |
| } |
| |
| AK_FORCE_INLINE uint32_t readField0(const int entryIndex) const { |
| return mBuffer.readUint(FIELD0_SIZE, ROOT_BITMAP_ENTRY_POS + entryIndex * ENTRY_SIZE); |
| } |
| |
| AK_FORCE_INLINE uint32_t readField1(const int entryIndex) const { |
| return mBuffer.readUint(FIELD1_SIZE, |
| ROOT_BITMAP_ENTRY_POS + entryIndex * ENTRY_SIZE + FIELD0_SIZE); |
| } |
| |
| AK_FORCE_INLINE int readEmptyTableLink(const int entryCount) const { |
| return mBuffer.readUint(FIELD1_SIZE, (entryCount - 1) * FIELD1_SIZE); |
| } |
| |
| AK_FORCE_INLINE bool writeEmptyTableLink(const int tableIndex, const int entryCount) { |
| return mBuffer.writeUint(tableIndex, FIELD1_SIZE, (entryCount - 1) * FIELD1_SIZE); |
| } |
| |
| AK_FORCE_INLINE bool writeField0(const uint32_t data, const int entryIndex) { |
| return mBuffer.writeUint(data, FIELD0_SIZE, |
| ROOT_BITMAP_ENTRY_POS + entryIndex * ENTRY_SIZE); |
| } |
| |
| AK_FORCE_INLINE bool writeField1(const uint32_t data, const int entryIndex) { |
| return mBuffer.writeUint(data, FIELD1_SIZE, |
| ROOT_BITMAP_ENTRY_POS + entryIndex * ENTRY_SIZE + FIELD0_SIZE); |
| } |
| |
| AK_FORCE_INLINE bool writeEntry(const Entry &entry, const int entryIndex) { |
| return writeField0(entry.mData0, entryIndex) && writeField1(entry.mData1, entryIndex); |
| } |
| |
| AK_FORCE_INLINE bool writeTerminalEntry(const uint32_t key, const uint64_t value, |
| const int entryIndex) { |
| return writeField0(key, entryIndex) && writeValue(value, entryIndex); |
| } |
| |
| AK_FORCE_INLINE bool copyEntry(const int originalEntryIndex, const int newEntryIndex) { |
| return writeEntry(readEntry(originalEntryIndex), newEntryIndex); |
| } |
| |
| AK_FORCE_INLINE int getTailEntryIndex() const { |
| return (mBuffer.getTailPosition() - ROOT_BITMAP_ENTRY_POS) / ENTRY_SIZE; |
| } |
| }; |
| |
| } // namespace latinime |
| #endif /* LATINIME_TRIE_MAP_H */ |