am 2c67361c: Merge "Move methods in BinaryFormat to PatriciaTriePolicy."
* commit '2c67361c165cf5f8be106d04aad038b48a08790e': Move methods in BinaryFormat to PatriciaTriePolicy.main
commit
d694477c3c
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@ -1,470 +0,0 @@
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/*
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* Copyright (C) 2011 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#ifndef LATINIME_BINARY_FORMAT_H
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#define LATINIME_BINARY_FORMAT_H
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#include <stdint.h>
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#include "suggest/core/dictionary/probability_utils.h"
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#include "utils/char_utils.h"
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namespace latinime {
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class BinaryFormat {
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public:
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// Mask and flags for children address type selection.
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static const int MASK_GROUP_ADDRESS_TYPE = 0xC0;
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// Flag for single/multiple char group
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static const int FLAG_HAS_MULTIPLE_CHARS = 0x20;
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// Flag for terminal groups
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static const int FLAG_IS_TERMINAL = 0x10;
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// Flag for shortcut targets presence
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static const int FLAG_HAS_SHORTCUT_TARGETS = 0x08;
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// Flag for bigram presence
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static const int FLAG_HAS_BIGRAMS = 0x04;
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// Flag for non-words (typically, shortcut only entries)
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static const int FLAG_IS_NOT_A_WORD = 0x02;
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// Flag for blacklist
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static const int FLAG_IS_BLACKLISTED = 0x01;
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// Attribute (bigram/shortcut) related flags:
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// Flag for presence of more attributes
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static const int FLAG_ATTRIBUTE_HAS_NEXT = 0x80;
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// Flag for sign of offset. If this flag is set, the offset value must be negated.
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static const int FLAG_ATTRIBUTE_OFFSET_NEGATIVE = 0x40;
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// Mask for attribute probability, stored on 4 bits inside the flags byte.
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static const int MASK_ATTRIBUTE_PROBABILITY = 0x0F;
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// Mask and flags for attribute address type selection.
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static const int MASK_ATTRIBUTE_ADDRESS_TYPE = 0x30;
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static int getGroupCountAndForwardPointer(const uint8_t *const dict, int *pos);
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static uint8_t getFlagsAndForwardPointer(const uint8_t *const dict, int *pos);
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static int getCodePointAndForwardPointer(const uint8_t *const dict, int *pos);
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static int readProbabilityWithoutMovingPointer(const uint8_t *const dict, const int pos);
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static int skipOtherCharacters(const uint8_t *const dict, const int pos);
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static int skipChildrenPosition(const uint8_t flags, const int pos);
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static int skipProbability(const uint8_t flags, const int pos);
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static int skipShortcuts(const uint8_t *const dict, const uint8_t flags, const int pos);
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static int skipChildrenPosAndAttributes(const uint8_t *const dict, const uint8_t flags,
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const int pos);
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static int readChildrenPosition(const uint8_t *const dict, const uint8_t flags, const int pos);
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static bool hasChildrenInFlags(const uint8_t flags);
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static int getTerminalPosition(const uint8_t *const root, const int *const inWord,
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const int length, const bool forceLowerCaseSearch);
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static int getCodePointsAndProbabilityAndReturnCodePointCount(
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const uint8_t *const root, const int nodePos, const int maxCodePointCount,
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int *const outCodePoints, int *const outUnigramProbability);
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private:
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DISALLOW_IMPLICIT_CONSTRUCTORS(BinaryFormat);
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static const int FLAG_GROUP_ADDRESS_TYPE_NOADDRESS = 0x00;
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static const int FLAG_GROUP_ADDRESS_TYPE_ONEBYTE = 0x40;
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static const int FLAG_GROUP_ADDRESS_TYPE_TWOBYTES = 0x80;
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static const int FLAG_GROUP_ADDRESS_TYPE_THREEBYTES = 0xC0;
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static const int FLAG_ATTRIBUTE_ADDRESS_TYPE_ONEBYTE = 0x10;
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static const int FLAG_ATTRIBUTE_ADDRESS_TYPE_TWOBYTES = 0x20;
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static const int FLAG_ATTRIBUTE_ADDRESS_TYPE_THREEBYTES = 0x30;
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static const int CHARACTER_ARRAY_TERMINATOR_SIZE = 1;
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static const int MINIMAL_ONE_BYTE_CHARACTER_VALUE = 0x20;
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static const int CHARACTER_ARRAY_TERMINATOR = 0x1F;
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static const int MULTIPLE_BYTE_CHARACTER_ADDITIONAL_SIZE = 2;
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static const int NO_FLAGS = 0;
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static int skipAllAttributes(const uint8_t *const dict, const uint8_t flags, const int pos);
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static int skipBigrams(const uint8_t *const dict, const uint8_t flags, const int pos);
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};
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AK_FORCE_INLINE int BinaryFormat::getGroupCountAndForwardPointer(const uint8_t *const dict,
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int *pos) {
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const int msb = dict[(*pos)++];
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if (msb < 0x80) return msb;
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return ((msb & 0x7F) << 8) | dict[(*pos)++];
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}
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inline uint8_t BinaryFormat::getFlagsAndForwardPointer(const uint8_t *const dict, int *pos) {
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return dict[(*pos)++];
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}
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AK_FORCE_INLINE int BinaryFormat::getCodePointAndForwardPointer(const uint8_t *const dict,
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int *pos) {
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const int origin = *pos;
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const int codePoint = dict[origin];
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if (codePoint < MINIMAL_ONE_BYTE_CHARACTER_VALUE) {
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if (codePoint == CHARACTER_ARRAY_TERMINATOR) {
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*pos = origin + 1;
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return NOT_A_CODE_POINT;
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} else {
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*pos = origin + 3;
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const int char_1 = codePoint << 16;
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const int char_2 = char_1 + (dict[origin + 1] << 8);
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return char_2 + dict[origin + 2];
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}
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} else {
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*pos = origin + 1;
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return codePoint;
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}
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}
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inline int BinaryFormat::readProbabilityWithoutMovingPointer(const uint8_t *const dict,
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const int pos) {
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return dict[pos];
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}
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AK_FORCE_INLINE int BinaryFormat::skipOtherCharacters(const uint8_t *const dict, const int pos) {
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int currentPos = pos;
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int character = dict[currentPos++];
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while (CHARACTER_ARRAY_TERMINATOR != character) {
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if (character < MINIMAL_ONE_BYTE_CHARACTER_VALUE) {
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currentPos += MULTIPLE_BYTE_CHARACTER_ADDITIONAL_SIZE;
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}
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character = dict[currentPos++];
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}
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return currentPos;
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}
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static inline int attributeAddressSize(const uint8_t flags) {
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static const int ATTRIBUTE_ADDRESS_SHIFT = 4;
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return (flags & BinaryFormat::MASK_ATTRIBUTE_ADDRESS_TYPE) >> ATTRIBUTE_ADDRESS_SHIFT;
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/* Note: this is a value-dependant optimization of what may probably be
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more readably written this way:
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switch (flags * BinaryFormat::MASK_ATTRIBUTE_ADDRESS_TYPE) {
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case FLAG_ATTRIBUTE_ADDRESS_TYPE_ONEBYTE: return 1;
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case FLAG_ATTRIBUTE_ADDRESS_TYPE_TWOBYTES: return 2;
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case FLAG_ATTRIBUTE_ADDRESS_TYPE_THREEBYTE: return 3;
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default: return 0;
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}
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*/
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}
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static AK_FORCE_INLINE int skipExistingBigrams(const uint8_t *const dict, const int pos) {
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int currentPos = pos;
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uint8_t flags = BinaryFormat::getFlagsAndForwardPointer(dict, ¤tPos);
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while (flags & BinaryFormat::FLAG_ATTRIBUTE_HAS_NEXT) {
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currentPos += attributeAddressSize(flags);
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flags = BinaryFormat::getFlagsAndForwardPointer(dict, ¤tPos);
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}
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currentPos += attributeAddressSize(flags);
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return currentPos;
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}
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static inline int childrenAddressSize(const uint8_t flags) {
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static const int CHILDREN_ADDRESS_SHIFT = 6;
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return (BinaryFormat::MASK_GROUP_ADDRESS_TYPE & flags) >> CHILDREN_ADDRESS_SHIFT;
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/* See the note in attributeAddressSize. The same applies here */
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}
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static AK_FORCE_INLINE int shortcutByteSize(const uint8_t *const dict, const int pos) {
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return (static_cast<int>(dict[pos] << 8)) + (dict[pos + 1]);
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}
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inline int BinaryFormat::skipChildrenPosition(const uint8_t flags, const int pos) {
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return pos + childrenAddressSize(flags);
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}
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inline int BinaryFormat::skipProbability(const uint8_t flags, const int pos) {
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return FLAG_IS_TERMINAL & flags ? pos + 1 : pos;
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}
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AK_FORCE_INLINE int BinaryFormat::skipShortcuts(const uint8_t *const dict, const uint8_t flags,
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const int pos) {
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if (FLAG_HAS_SHORTCUT_TARGETS & flags) {
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return pos + shortcutByteSize(dict, pos);
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} else {
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return pos;
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}
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}
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AK_FORCE_INLINE int BinaryFormat::skipBigrams(const uint8_t *const dict, const uint8_t flags,
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const int pos) {
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if (FLAG_HAS_BIGRAMS & flags) {
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return skipExistingBigrams(dict, pos);
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} else {
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return pos;
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}
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}
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AK_FORCE_INLINE int BinaryFormat::skipAllAttributes(const uint8_t *const dict, const uint8_t flags,
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const int pos) {
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// This function skips all attributes: shortcuts and bigrams.
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int newPos = pos;
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newPos = skipShortcuts(dict, flags, newPos);
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newPos = skipBigrams(dict, flags, newPos);
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return newPos;
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}
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AK_FORCE_INLINE int BinaryFormat::skipChildrenPosAndAttributes(const uint8_t *const dict,
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const uint8_t flags, const int pos) {
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int currentPos = pos;
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currentPos = skipChildrenPosition(flags, currentPos);
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currentPos = skipAllAttributes(dict, flags, currentPos);
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return currentPos;
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}
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AK_FORCE_INLINE int BinaryFormat::readChildrenPosition(const uint8_t *const dict,
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const uint8_t flags, const int pos) {
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int offset = 0;
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switch (MASK_GROUP_ADDRESS_TYPE & flags) {
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case FLAG_GROUP_ADDRESS_TYPE_ONEBYTE:
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offset = dict[pos];
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break;
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case FLAG_GROUP_ADDRESS_TYPE_TWOBYTES:
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offset = dict[pos] << 8;
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offset += dict[pos + 1];
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break;
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case FLAG_GROUP_ADDRESS_TYPE_THREEBYTES:
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offset = dict[pos] << 16;
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offset += dict[pos + 1] << 8;
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offset += dict[pos + 2];
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break;
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default:
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// If we come here, it means we asked for the children of a word with
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// no children.
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return -1;
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}
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return pos + offset;
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}
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inline bool BinaryFormat::hasChildrenInFlags(const uint8_t flags) {
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return (FLAG_GROUP_ADDRESS_TYPE_NOADDRESS != (MASK_GROUP_ADDRESS_TYPE & flags));
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}
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// This function gets the byte position of the last chargroup of the exact matching word in the
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// dictionary. If no match is found, it returns NOT_A_VALID_WORD_POS.
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AK_FORCE_INLINE int BinaryFormat::getTerminalPosition(const uint8_t *const root,
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const int *const inWord, const int length, const bool forceLowerCaseSearch) {
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int pos = 0;
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int wordPos = 0;
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while (true) {
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// If we already traversed the tree further than the word is long, there means
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// there was no match (or we would have found it).
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if (wordPos >= length) return NOT_A_VALID_WORD_POS;
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int charGroupCount = BinaryFormat::getGroupCountAndForwardPointer(root, &pos);
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const int wChar = forceLowerCaseSearch
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? CharUtils::toLowerCase(inWord[wordPos]) : inWord[wordPos];
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while (true) {
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// If there are no more character groups in this node, it means we could not
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// find a matching character for this depth, therefore there is no match.
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if (0 >= charGroupCount) return NOT_A_VALID_WORD_POS;
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const int charGroupPos = pos;
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const uint8_t flags = BinaryFormat::getFlagsAndForwardPointer(root, &pos);
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int character = BinaryFormat::getCodePointAndForwardPointer(root, &pos);
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if (character == wChar) {
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// This is the correct node. Only one character group may start with the same
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// char within a node, so either we found our match in this node, or there is
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// no match and we can return NOT_A_VALID_WORD_POS. So we will check all the
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// characters in this character group indeed does match.
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if (FLAG_HAS_MULTIPLE_CHARS & flags) {
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character = BinaryFormat::getCodePointAndForwardPointer(root, &pos);
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while (NOT_A_CODE_POINT != character) {
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++wordPos;
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// If we shoot the length of the word we search for, or if we find a single
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// character that does not match, as explained above, it means the word is
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// not in the dictionary (by virtue of this chargroup being the only one to
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// match the word on the first character, but not matching the whole word).
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if (wordPos >= length) return NOT_A_VALID_WORD_POS;
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if (inWord[wordPos] != character) return NOT_A_VALID_WORD_POS;
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character = BinaryFormat::getCodePointAndForwardPointer(root, &pos);
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}
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}
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// If we come here we know that so far, we do match. Either we are on a terminal
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// and we match the length, in which case we found it, or we traverse children.
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// If we don't match the length AND don't have children, then a word in the
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// dictionary fully matches a prefix of the searched word but not the full word.
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++wordPos;
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if (FLAG_IS_TERMINAL & flags) {
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if (wordPos == length) {
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return charGroupPos;
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}
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pos = BinaryFormat::skipProbability(FLAG_IS_TERMINAL, pos);
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}
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if (FLAG_GROUP_ADDRESS_TYPE_NOADDRESS == (MASK_GROUP_ADDRESS_TYPE & flags)) {
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return NOT_A_VALID_WORD_POS;
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}
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// We have children and we are still shorter than the word we are searching for, so
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// we need to traverse children. Put the pointer on the children position, and
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// break
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pos = BinaryFormat::readChildrenPosition(root, flags, pos);
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break;
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} else {
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// This chargroup does not match, so skip the remaining part and go to the next.
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if (FLAG_HAS_MULTIPLE_CHARS & flags) {
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pos = BinaryFormat::skipOtherCharacters(root, pos);
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}
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pos = BinaryFormat::skipProbability(flags, pos);
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pos = BinaryFormat::skipChildrenPosAndAttributes(root, flags, pos);
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}
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--charGroupCount;
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}
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}
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}
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// This function searches for a terminal in the dictionary by its address.
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// Due to the fact that words are ordered in the dictionary in a strict breadth-first order,
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// it is possible to check for this with advantageous complexity. For each node, we search
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// for groups with children and compare the children address with the address we look for.
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// When we shoot the address we look for, it means the word we look for is in the children
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// of the previous group. The only tricky part is the fact that if we arrive at the end of a
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// node with the last group's children address still less than what we are searching for, we
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// must descend the last group's children (for example, if the word we are searching for starts
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// with a z, it's the last group of the root node, so all children addresses will be smaller
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// than the address we look for, and we have to descend the z node).
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/* Parameters :
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* root: the dictionary buffer
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* address: the byte position of the last chargroup of the word we are searching for (this is
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* what is stored as the "bigram address" in each bigram)
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* outword: an array to write the found word, with MAX_WORD_LENGTH size.
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* outUnigramProbability: a pointer to an int to write the probability into.
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* Return value : the length of the word, of 0 if the word was not found.
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*/
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AK_FORCE_INLINE int BinaryFormat::getCodePointsAndProbabilityAndReturnCodePointCount(
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const uint8_t *const root, const int nodePos, const int maxCodePointCount,
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int *const outCodePoints, int *const outUnigramProbability) {
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int pos = 0;
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int wordPos = 0;
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// One iteration of the outer loop iterates through nodes. As stated above, we will only
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// traverse nodes that are actually a part of the terminal we are searching, so each time
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// we enter this loop we are one depth level further than last time.
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// The only reason we count nodes is because we want to reduce the probability of infinite
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// looping in case there is a bug. Since we know there is an upper bound to the depth we are
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// supposed to traverse, it does not hurt to count iterations.
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for (int loopCount = maxCodePointCount; loopCount > 0; --loopCount) {
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int lastCandidateGroupPos = 0;
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// Let's loop through char groups in this node searching for either the terminal
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// or one of its ascendants.
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for (int charGroupCount = getGroupCountAndForwardPointer(root, &pos); charGroupCount > 0;
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--charGroupCount) {
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const int startPos = pos;
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const uint8_t flags = getFlagsAndForwardPointer(root, &pos);
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const int character = getCodePointAndForwardPointer(root, &pos);
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if (nodePos == startPos) {
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// We found the address. Copy the rest of the word in the buffer and return
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// the length.
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outCodePoints[wordPos] = character;
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if (FLAG_HAS_MULTIPLE_CHARS & flags) {
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int nextChar = getCodePointAndForwardPointer(root, &pos);
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// We count chars in order to avoid infinite loops if the file is broken or
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// if there is some other bug
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int charCount = maxCodePointCount;
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while (NOT_A_CODE_POINT != nextChar && --charCount > 0) {
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outCodePoints[++wordPos] = nextChar;
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nextChar = getCodePointAndForwardPointer(root, &pos);
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}
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}
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*outUnigramProbability = readProbabilityWithoutMovingPointer(root, pos);
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return ++wordPos;
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}
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// We need to skip past this char group, so skip any remaining chars after the
|
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// first and possibly the probability.
|
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if (FLAG_HAS_MULTIPLE_CHARS & flags) {
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pos = skipOtherCharacters(root, pos);
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}
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pos = skipProbability(flags, pos);
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// The fact that this group has children is very important. Since we already know
|
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// that this group does not match, if it has no children we know it is irrelevant
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||||
// to what we are searching for.
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const bool hasChildren = (FLAG_GROUP_ADDRESS_TYPE_NOADDRESS !=
|
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(MASK_GROUP_ADDRESS_TYPE & flags));
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||||
// We will write in `found' whether we have passed the children address we are
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||||
// searching for. For example if we search for "beer", the children of b are less
|
||||
// than the address we are searching for and the children of c are greater. When we
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||||
// come here for c, we realize this is too big, and that we should descend b.
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||||
bool found;
|
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if (hasChildren) {
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||||
// Here comes the tricky part. First, read the children position.
|
||||
const int childrenPos = readChildrenPosition(root, flags, pos);
|
||||
if (childrenPos > nodePos) {
|
||||
// If the children pos is greater than address, it means the previous chargroup,
|
||||
// which address is stored in lastCandidateGroupPos, was the right one.
|
||||
found = true;
|
||||
} else if (1 >= charGroupCount) {
|
||||
// However if we are on the LAST group of this node, and we have NOT shot the
|
||||
// address we should descend THIS node. So we trick the lastCandidateGroupPos
|
||||
// so that we will descend this node, not the previous one.
|
||||
lastCandidateGroupPos = startPos;
|
||||
found = true;
|
||||
} else {
|
||||
// Else, we should continue looking.
|
||||
found = false;
|
||||
}
|
||||
} else {
|
||||
// Even if we don't have children here, we could still be on the last group of this
|
||||
// node. If this is the case, we should descend the last group that had children,
|
||||
// and their address is already in lastCandidateGroup.
|
||||
found = (1 >= charGroupCount);
|
||||
}
|
||||
|
||||
if (found) {
|
||||
// Okay, we found the group we should descend. Its address is in
|
||||
// the lastCandidateGroupPos variable, so we just re-read it.
|
||||
if (0 != lastCandidateGroupPos) {
|
||||
const uint8_t lastFlags =
|
||||
getFlagsAndForwardPointer(root, &lastCandidateGroupPos);
|
||||
const int lastChar =
|
||||
getCodePointAndForwardPointer(root, &lastCandidateGroupPos);
|
||||
// We copy all the characters in this group to the buffer
|
||||
outCodePoints[wordPos] = lastChar;
|
||||
if (FLAG_HAS_MULTIPLE_CHARS & lastFlags) {
|
||||
int nextChar = getCodePointAndForwardPointer(root, &lastCandidateGroupPos);
|
||||
int charCount = maxCodePointCount;
|
||||
while (-1 != nextChar && --charCount > 0) {
|
||||
outCodePoints[++wordPos] = nextChar;
|
||||
nextChar = getCodePointAndForwardPointer(root, &lastCandidateGroupPos);
|
||||
}
|
||||
}
|
||||
++wordPos;
|
||||
// Now we only need to branch to the children address. Skip the probability if
|
||||
// it's there, read pos, and break to resume the search at pos.
|
||||
lastCandidateGroupPos = skipProbability(lastFlags, lastCandidateGroupPos);
|
||||
pos = readChildrenPosition(root, lastFlags, lastCandidateGroupPos);
|
||||
break;
|
||||
} else {
|
||||
// Here is a little tricky part: we come here if we found out that all children
|
||||
// addresses in this group are bigger than the address we are searching for.
|
||||
// Should we conclude the word is not in the dictionary? No! It could still be
|
||||
// one of the remaining chargroups in this node, so we have to keep looking in
|
||||
// this node until we find it (or we realize it's not there either, in which
|
||||
// case it's actually not in the dictionary). Pass the end of this group, ready
|
||||
// to start the next one.
|
||||
pos = skipChildrenPosAndAttributes(root, flags, pos);
|
||||
}
|
||||
} else {
|
||||
// If we did not find it, we should record the last children address for the next
|
||||
// iteration.
|
||||
if (hasChildren) lastCandidateGroupPos = startPos;
|
||||
// Now skip the end of this group (children pos and the attributes if any) so that
|
||||
// our pos is after the end of this char group, at the start of the next one.
|
||||
pos = skipChildrenPosAndAttributes(root, flags, pos);
|
||||
}
|
||||
|
||||
}
|
||||
}
|
||||
// If we have looked through all the chargroups and found no match, the address is
|
||||
// not the address of a terminal in this dictionary.
|
||||
return 0;
|
||||
}
|
||||
|
||||
} // namespace latinime
|
||||
#endif // LATINIME_BINARY_FORMAT_H
|
|
@ -20,7 +20,6 @@
|
|||
#include "defines.h"
|
||||
#include "suggest/core/dicnode/dic_node.h"
|
||||
#include "suggest/core/dicnode/dic_node_vector.h"
|
||||
#include "suggest/policyimpl/dictionary/binary_format.h"
|
||||
#include "suggest/policyimpl/dictionary/patricia_trie_reading_utils.h"
|
||||
|
||||
namespace latinime {
|
||||
|
@ -38,17 +37,273 @@ void PatriciaTriePolicy::createAndGetAllChildNodes(const DicNode *const dicNode,
|
|||
}
|
||||
}
|
||||
|
||||
// This retrieves code points and the probability of the word by its terminal position.
|
||||
// Due to the fact that words are ordered in the dictionary in a strict breadth-first order,
|
||||
// it is possible to check for this with advantageous complexity. For each node, we search
|
||||
// for groups with children and compare the children position with the position we look for.
|
||||
// When we shoot the position we look for, it means the word we look for is in the children
|
||||
// of the previous group. The only tricky part is the fact that if we arrive at the end of a
|
||||
// node with the last group's children position still less than what we are searching for, we
|
||||
// must descend the last group's children (for example, if the word we are searching for starts
|
||||
// with a z, it's the last group of the root node, so all children addresses will be smaller
|
||||
// than the position we look for, and we have to descend the z node).
|
||||
/* Parameters :
|
||||
* nodePos: the byte position of the terminal chargroup of the word we are searching for (this is
|
||||
* what is stored as the "bigram position" in each bigram)
|
||||
* outCodePoints: an array to write the found word, with MAX_WORD_LENGTH size.
|
||||
* outUnigramProbability: a pointer to an int to write the probability into.
|
||||
* Return value : the code point count, of 0 if the word was not found.
|
||||
*/
|
||||
// TODO: Split this function to be more readable
|
||||
int PatriciaTriePolicy::getCodePointsAndProbabilityAndReturnCodePointCount(
|
||||
const int nodePos, const int maxCodePointCount, int *const outCodePoints,
|
||||
int *const outUnigramProbability) const {
|
||||
return BinaryFormat::getCodePointsAndProbabilityAndReturnCodePointCount(mDictRoot, nodePos,
|
||||
maxCodePointCount, outCodePoints, outUnigramProbability);
|
||||
int pos = getRootPosition();
|
||||
int wordPos = 0;
|
||||
// One iteration of the outer loop iterates through nodes. As stated above, we will only
|
||||
// traverse nodes that are actually a part of the terminal we are searching, so each time
|
||||
// we enter this loop we are one depth level further than last time.
|
||||
// The only reason we count nodes is because we want to reduce the probability of infinite
|
||||
// looping in case there is a bug. Since we know there is an upper bound to the depth we are
|
||||
// supposed to traverse, it does not hurt to count iterations.
|
||||
for (int loopCount = maxCodePointCount; loopCount > 0; --loopCount) {
|
||||
int lastCandidateGroupPos = 0;
|
||||
// Let's loop through char groups in this node searching for either the terminal
|
||||
// or one of its ascendants.
|
||||
for (int charGroupCount = PatriciaTrieReadingUtils::getGroupCountAndAdvancePosition(
|
||||
mDictRoot, &pos); charGroupCount > 0; --charGroupCount) {
|
||||
const int startPos = pos;
|
||||
const PatriciaTrieReadingUtils::NodeFlags flags =
|
||||
PatriciaTrieReadingUtils::getFlagsAndAdvancePosition(mDictRoot, &pos);
|
||||
const int character = PatriciaTrieReadingUtils::getCodePointAndAdvancePosition(
|
||||
mDictRoot, &pos);
|
||||
if (nodePos == startPos) {
|
||||
// We found the position. Copy the rest of the code points in the buffer and return
|
||||
// the length.
|
||||
outCodePoints[wordPos] = character;
|
||||
if (PatriciaTrieReadingUtils::hasMultipleChars(flags)) {
|
||||
int nextChar = PatriciaTrieReadingUtils::getCodePointAndAdvancePosition(
|
||||
mDictRoot, &pos);
|
||||
// We count code points in order to avoid infinite loops if the file is broken
|
||||
// or if there is some other bug
|
||||
int charCount = maxCodePointCount;
|
||||
while (NOT_A_CODE_POINT != nextChar && --charCount > 0) {
|
||||
outCodePoints[++wordPos] = nextChar;
|
||||
nextChar = PatriciaTrieReadingUtils::getCodePointAndAdvancePosition(
|
||||
mDictRoot, &pos);
|
||||
}
|
||||
}
|
||||
*outUnigramProbability =
|
||||
PatriciaTrieReadingUtils::readProbabilityAndAdvancePosition(mDictRoot,
|
||||
&pos);
|
||||
return ++wordPos;
|
||||
}
|
||||
// We need to skip past this char group, so skip any remaining code points after the
|
||||
// first and possibly the probability.
|
||||
if (PatriciaTrieReadingUtils::hasMultipleChars(flags)) {
|
||||
PatriciaTrieReadingUtils::skipCharacters(mDictRoot, flags, MAX_WORD_LENGTH, &pos);
|
||||
}
|
||||
if (PatriciaTrieReadingUtils::isTerminal(flags)) {
|
||||
PatriciaTrieReadingUtils::readProbabilityAndAdvancePosition(mDictRoot, &pos);
|
||||
}
|
||||
// The fact that this group has children is very important. Since we already know
|
||||
// that this group does not match, if it has no children we know it is irrelevant
|
||||
// to what we are searching for.
|
||||
const bool hasChildren = PatriciaTrieReadingUtils::hasChildrenInFlags(flags);
|
||||
// We will write in `found' whether we have passed the children position we are
|
||||
// searching for. For example if we search for "beer", the children of b are less
|
||||
// than the address we are searching for and the children of c are greater. When we
|
||||
// come here for c, we realize this is too big, and that we should descend b.
|
||||
bool found;
|
||||
if (hasChildren) {
|
||||
int currentPos = pos;
|
||||
// Here comes the tricky part. First, read the children position.
|
||||
const int childrenPos = PatriciaTrieReadingUtils
|
||||
::readChildrenPositionAndAdvancePosition(mDictRoot, flags, ¤tPos);
|
||||
if (childrenPos > nodePos) {
|
||||
// If the children pos is greater than the position, it means the previous
|
||||
// chargroup, which position is stored in lastCandidateGroupPos, was the right
|
||||
// one.
|
||||
found = true;
|
||||
} else if (1 >= charGroupCount) {
|
||||
// However if we are on the LAST group of this node, and we have NOT shot the
|
||||
// position we should descend THIS node. So we trick the lastCandidateGroupPos
|
||||
// so that we will descend this node, not the previous one.
|
||||
lastCandidateGroupPos = startPos;
|
||||
found = true;
|
||||
} else {
|
||||
// Else, we should continue looking.
|
||||
found = false;
|
||||
}
|
||||
} else {
|
||||
// Even if we don't have children here, we could still be on the last group of this
|
||||
// node. If this is the case, we should descend the last group that had children,
|
||||
// and their position is already in lastCandidateGroup.
|
||||
found = (1 >= charGroupCount);
|
||||
}
|
||||
|
||||
if (found) {
|
||||
// Okay, we found the group we should descend. Its position is in
|
||||
// the lastCandidateGroupPos variable, so we just re-read it.
|
||||
if (0 != lastCandidateGroupPos) {
|
||||
const PatriciaTrieReadingUtils::NodeFlags lastFlags =
|
||||
PatriciaTrieReadingUtils::getFlagsAndAdvancePosition(
|
||||
mDictRoot, &lastCandidateGroupPos);
|
||||
const int lastChar = PatriciaTrieReadingUtils::getCodePointAndAdvancePosition(
|
||||
mDictRoot, &lastCandidateGroupPos);
|
||||
// We copy all the characters in this group to the buffer
|
||||
outCodePoints[wordPos] = lastChar;
|
||||
if (PatriciaTrieReadingUtils::hasMultipleChars(lastFlags)) {
|
||||
int nextChar = PatriciaTrieReadingUtils::getCodePointAndAdvancePosition(
|
||||
mDictRoot, &lastCandidateGroupPos);
|
||||
int charCount = maxCodePointCount;
|
||||
while (-1 != nextChar && --charCount > 0) {
|
||||
outCodePoints[++wordPos] = nextChar;
|
||||
nextChar = PatriciaTrieReadingUtils::getCodePointAndAdvancePosition(
|
||||
mDictRoot, &lastCandidateGroupPos);
|
||||
}
|
||||
}
|
||||
++wordPos;
|
||||
// Now we only need to branch to the children address. Skip the probability if
|
||||
// it's there, read pos, and break to resume the search at pos.
|
||||
if (PatriciaTrieReadingUtils::isTerminal(lastFlags)) {
|
||||
PatriciaTrieReadingUtils::readProbabilityAndAdvancePosition(mDictRoot,
|
||||
&lastCandidateGroupPos);
|
||||
}
|
||||
pos = PatriciaTrieReadingUtils::readChildrenPositionAndAdvancePosition(
|
||||
mDictRoot, lastFlags, &lastCandidateGroupPos);
|
||||
break;
|
||||
} else {
|
||||
// Here is a little tricky part: we come here if we found out that all children
|
||||
// addresses in this group are bigger than the address we are searching for.
|
||||
// Should we conclude the word is not in the dictionary? No! It could still be
|
||||
// one of the remaining chargroups in this node, so we have to keep looking in
|
||||
// this node until we find it (or we realize it's not there either, in which
|
||||
// case it's actually not in the dictionary). Pass the end of this group, ready
|
||||
// to start the next one.
|
||||
if (PatriciaTrieReadingUtils::hasChildrenInFlags(flags)) {
|
||||
PatriciaTrieReadingUtils::readChildrenPositionAndAdvancePosition(
|
||||
mDictRoot, flags, &pos);
|
||||
}
|
||||
if (PatriciaTrieReadingUtils::hasShortcutTargets(flags)) {
|
||||
mShortcutListPolicy.skipAllShortcuts(&pos);
|
||||
}
|
||||
if (PatriciaTrieReadingUtils::hasBigrams(flags)) {
|
||||
mBigramListPolicy.skipAllBigrams(&pos);
|
||||
}
|
||||
}
|
||||
} else {
|
||||
// If we did not find it, we should record the last children address for the next
|
||||
// iteration.
|
||||
if (hasChildren) lastCandidateGroupPos = startPos;
|
||||
// Now skip the end of this group (children pos and the attributes if any) so that
|
||||
// our pos is after the end of this char group, at the start of the next one.
|
||||
if (PatriciaTrieReadingUtils::hasChildrenInFlags(flags)) {
|
||||
PatriciaTrieReadingUtils::readChildrenPositionAndAdvancePosition(
|
||||
mDictRoot, flags, &pos);
|
||||
}
|
||||
if (PatriciaTrieReadingUtils::hasShortcutTargets(flags)) {
|
||||
mShortcutListPolicy.skipAllShortcuts(&pos);
|
||||
}
|
||||
if (PatriciaTrieReadingUtils::hasBigrams(flags)) {
|
||||
mBigramListPolicy.skipAllBigrams(&pos);
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
}
|
||||
// If we have looked through all the chargroups and found no match, the nodePos is
|
||||
// not the position of a terminal in this dictionary.
|
||||
return 0;
|
||||
}
|
||||
|
||||
// This function gets the position of the terminal node of the exact matching word in the
|
||||
// dictionary. If no match is found, it returns NOT_A_VALID_WORD_POS.
|
||||
int PatriciaTriePolicy::getTerminalNodePositionOfWord(const int *const inWord,
|
||||
const int length, const bool forceLowerCaseSearch) const {
|
||||
return BinaryFormat::getTerminalPosition(mDictRoot, inWord,
|
||||
length, forceLowerCaseSearch);
|
||||
int pos = getRootPosition();
|
||||
int wordPos = 0;
|
||||
|
||||
while (true) {
|
||||
// If we already traversed the tree further than the word is long, there means
|
||||
// there was no match (or we would have found it).
|
||||
if (wordPos >= length) return NOT_A_VALID_WORD_POS;
|
||||
int charGroupCount = PatriciaTrieReadingUtils::getGroupCountAndAdvancePosition(mDictRoot,
|
||||
&pos);
|
||||
const int wChar = forceLowerCaseSearch
|
||||
? CharUtils::toLowerCase(inWord[wordPos]) : inWord[wordPos];
|
||||
while (true) {
|
||||
// If there are no more character groups in this node, it means we could not
|
||||
// find a matching character for this depth, therefore there is no match.
|
||||
if (0 >= charGroupCount) return NOT_A_VALID_WORD_POS;
|
||||
const int charGroupPos = pos;
|
||||
const PatriciaTrieReadingUtils::NodeFlags flags =
|
||||
PatriciaTrieReadingUtils::getFlagsAndAdvancePosition(mDictRoot, &pos);
|
||||
int character = PatriciaTrieReadingUtils::getCodePointAndAdvancePosition(mDictRoot,
|
||||
&pos);
|
||||
if (character == wChar) {
|
||||
// This is the correct node. Only one character group may start with the same
|
||||
// char within a node, so either we found our match in this node, or there is
|
||||
// no match and we can return NOT_A_VALID_WORD_POS. So we will check all the
|
||||
// characters in this character group indeed does match.
|
||||
if (PatriciaTrieReadingUtils::hasMultipleChars(flags)) {
|
||||
character = PatriciaTrieReadingUtils::getCodePointAndAdvancePosition(mDictRoot,
|
||||
&pos);
|
||||
while (NOT_A_CODE_POINT != character) {
|
||||
++wordPos;
|
||||
// If we shoot the length of the word we search for, or if we find a single
|
||||
// character that does not match, as explained above, it means the word is
|
||||
// not in the dictionary (by virtue of this chargroup being the only one to
|
||||
// match the word on the first character, but not matching the whole word).
|
||||
if (wordPos >= length) return NOT_A_VALID_WORD_POS;
|
||||
if (inWord[wordPos] != character) return NOT_A_VALID_WORD_POS;
|
||||
character = PatriciaTrieReadingUtils::getCodePointAndAdvancePosition(
|
||||
mDictRoot, &pos);
|
||||
}
|
||||
}
|
||||
// If we come here we know that so far, we do match. Either we are on a terminal
|
||||
// and we match the length, in which case we found it, or we traverse children.
|
||||
// If we don't match the length AND don't have children, then a word in the
|
||||
// dictionary fully matches a prefix of the searched word but not the full word.
|
||||
++wordPos;
|
||||
if (PatriciaTrieReadingUtils::isTerminal(flags)) {
|
||||
if (wordPos == length) {
|
||||
return charGroupPos;
|
||||
}
|
||||
PatriciaTrieReadingUtils::readProbabilityAndAdvancePosition(mDictRoot, &pos);
|
||||
}
|
||||
if (!PatriciaTrieReadingUtils::hasChildrenInFlags(flags)) {
|
||||
return NOT_A_VALID_WORD_POS;
|
||||
}
|
||||
// We have children and we are still shorter than the word we are searching for, so
|
||||
// we need to traverse children. Put the pointer on the children position, and
|
||||
// break
|
||||
pos = PatriciaTrieReadingUtils::readChildrenPositionAndAdvancePosition(mDictRoot,
|
||||
flags, &pos);
|
||||
break;
|
||||
} else {
|
||||
// This chargroup does not match, so skip the remaining part and go to the next.
|
||||
if (PatriciaTrieReadingUtils::hasMultipleChars(flags)) {
|
||||
PatriciaTrieReadingUtils::skipCharacters(mDictRoot, flags, MAX_WORD_LENGTH,
|
||||
&pos);
|
||||
}
|
||||
if (PatriciaTrieReadingUtils::isTerminal(flags)) {
|
||||
PatriciaTrieReadingUtils::readProbabilityAndAdvancePosition(mDictRoot, &pos);
|
||||
}
|
||||
if (PatriciaTrieReadingUtils::hasChildrenInFlags(flags)) {
|
||||
PatriciaTrieReadingUtils::readChildrenPositionAndAdvancePosition(mDictRoot,
|
||||
flags, &pos);
|
||||
}
|
||||
if (PatriciaTrieReadingUtils::hasShortcutTargets(flags)) {
|
||||
mShortcutListPolicy.skipAllShortcuts(&pos);
|
||||
}
|
||||
if (PatriciaTrieReadingUtils::hasBigrams(flags)) {
|
||||
mBigramListPolicy.skipAllBigrams(&pos);
|
||||
}
|
||||
}
|
||||
--charGroupCount;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
int PatriciaTriePolicy::getUnigramProbability(const int nodePos) const {
|
||||
|
|
Loading…
Reference in New Issue