Merge "Avoid copying bigram list if possible."

This commit is contained in:
Keisuke Kuroyanagi 2014-05-09 10:09:53 +00:00 committed by Android (Google) Code Review
commit b7f71cdf8c
3 changed files with 66 additions and 41 deletions

View File

@ -50,12 +50,18 @@ void Ver4BigramListPolicy::getNextBigram(int *const outBigramPos, int *const out
bool Ver4BigramListPolicy::addNewEntry(const int terminalId, const int newTargetTerminalId,
const int newProbability, const int timestamp, bool *const outAddedNewEntry) {
// 1. The word has no bigrams yet.
// 2. The word has bigrams, and there is the target in the list.
// 3. The word has bigrams, and there is an invalid entry that can be reclaimed.
// 4. The word has bigrams. We have to append new bigram entry to the list.
// 5. Same as 4, but the list is the last entry of the content file.
if (outAddedNewEntry) {
*outAddedNewEntry = false;
}
const int bigramListPos = mBigramDictContent->getBigramListHeadPos(terminalId);
if (bigramListPos == NOT_A_DICT_POS) {
// Updating PtNode that doesn't have a bigram list.
// Case 1. PtNode that doesn't have a bigram list.
// Create new bigram list.
if (!mBigramDictContent->createNewBigramList(terminalId)) {
return false;
@ -75,50 +81,55 @@ bool Ver4BigramListPolicy::addNewEntry(const int terminalId, const int newTarget
return true;
}
const int entryPosToUpdate = getEntryPosToUpdate(newTargetTerminalId, bigramListPos);
if (entryPosToUpdate != NOT_A_DICT_POS) {
// Overwrite existing entry.
const BigramEntry originalBigramEntry =
mBigramDictContent->getBigramEntry(entryPosToUpdate);
if (!originalBigramEntry.isValid()) {
// Reuse invalid entry.
if (outAddedNewEntry) {
*outAddedNewEntry = true;
int tailEntryPos = NOT_A_DICT_POS;
const int entryPosToUpdate = getEntryPosToUpdate(newTargetTerminalId, bigramListPos,
&tailEntryPos);
if (tailEntryPos != NOT_A_DICT_POS || entryPosToUpdate == NOT_A_DICT_POS) {
// Case 4, 5.
// Add new entry to the bigram list.
if (tailEntryPos == NOT_A_DICT_POS) {
// Case 4. Create new bigram list.
if (!mBigramDictContent->createNewBigramList(terminalId)) {
return false;
}
const int destPos = mBigramDictContent->getBigramListHeadPos(terminalId);
// Copy existing bigram list.
if (!mBigramDictContent->copyBigramList(bigramListPos, destPos, &tailEntryPos)) {
return false;
}
}
const BigramEntry updatedBigramEntry =
originalBigramEntry.updateTargetTerminalIdAndGetEntry(newTargetTerminalId);
// Write new entry at the tail position of the bigram content.
const BigramEntry newBigramEntry(false /* hasNext */, NOT_A_PROBABILITY,
newTargetTerminalId);
const BigramEntry bigramEntryToWrite = createUpdatedBigramEntryFrom(
&updatedBigramEntry, newProbability, timestamp);
return mBigramDictContent->writeBigramEntry(&bigramEntryToWrite, entryPosToUpdate);
&newBigramEntry, newProbability, timestamp);
if (!mBigramDictContent->writeBigramEntryAtTail(&bigramEntryToWrite)) {
return false;
}
// Update has next flag of the tail entry.
if (!updateHasNextFlag(true /* hasNext */, tailEntryPos)) {
return false;
}
if (outAddedNewEntry) {
*outAddedNewEntry = true;
}
return true;
}
// Add new entry to the bigram list.
// Create new bigram list.
if (!mBigramDictContent->createNewBigramList(terminalId)) {
return false;
// Case 2. Overwrite the existing entry. Case 3. Reclaim and reuse the existing invalid entry.
const BigramEntry originalBigramEntry = mBigramDictContent->getBigramEntry(entryPosToUpdate);
if (!originalBigramEntry.isValid()) {
// Case 3. Reuse the existing invalid entry. outAddedNewEntry is false when an existing
// entry is updated.
if (outAddedNewEntry) {
*outAddedNewEntry = true;
}
}
int writingPos = mBigramDictContent->getBigramListHeadPos(terminalId);
int tailEntryPos = NOT_A_DICT_POS;
// Copy existing bigram list.
if (!mBigramDictContent->copyBigramList(bigramListPos, writingPos, &tailEntryPos)) {
return false;
}
// Write new entry at the tail position of the bigram content.
const BigramEntry newBigramEntry(false /* hasNext */, NOT_A_PROBABILITY, newTargetTerminalId);
const BigramEntry updatedBigramEntry =
originalBigramEntry.updateTargetTerminalIdAndGetEntry(newTargetTerminalId);
const BigramEntry bigramEntryToWrite = createUpdatedBigramEntryFrom(
&newBigramEntry, newProbability, timestamp);
if (!mBigramDictContent->writeBigramEntryAtTail(&bigramEntryToWrite)) {
return false;
}
// Update has next flag of the tail entry.
if (!updateHasNextFlag(true /* hasNext */, tailEntryPos)) {
return false;
}
if (outAddedNewEntry) {
*outAddedNewEntry = true;
}
return true;
&updatedBigramEntry, newProbability, timestamp);
return mBigramDictContent->writeBigramEntry(&bigramEntryToWrite, entryPosToUpdate);
}
bool Ver4BigramListPolicy::removeEntry(const int terminalId, const int targetTerminalId) {
@ -127,7 +138,8 @@ bool Ver4BigramListPolicy::removeEntry(const int terminalId, const int targetTer
// Bigram list doesn't exist.
return false;
}
const int entryPosToUpdate = getEntryPosToUpdate(targetTerminalId, bigramListPos);
const int entryPosToUpdate = getEntryPosToUpdate(targetTerminalId, bigramListPos,
nullptr /* outTailEntryPos */);
if (entryPosToUpdate == NOT_A_DICT_POS) {
// Bigram entry doesn't exist.
return false;
@ -212,7 +224,10 @@ int Ver4BigramListPolicy::getBigramEntryConut(const int terminalId) {
}
int Ver4BigramListPolicy::getEntryPosToUpdate(const int targetTerminalIdToFind,
const int bigramListPos) const {
const int bigramListPos, int *const outTailEntryPos) const {
if (outTailEntryPos) {
*outTailEntryPos = NOT_A_DICT_POS;
}
bool hasNext = true;
int invalidEntryPos = NOT_A_DICT_POS;
int readingPos = bigramListPos;
@ -228,6 +243,11 @@ int Ver4BigramListPolicy::getEntryPosToUpdate(const int targetTerminalIdToFind,
// Invalid entry that can be reused is found.
invalidEntryPos = entryPos;
}
if (!hasNext && mBigramDictContent->isContentTailPos(readingPos)) {
if (outTailEntryPos) {
*outTailEntryPos = entryPos;
}
}
}
return invalidEntryPos;
}

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@ -56,7 +56,8 @@ class Ver4BigramListPolicy : public DictionaryBigramsStructurePolicy {
private:
DISALLOW_IMPLICIT_CONSTRUCTORS(Ver4BigramListPolicy);
int getEntryPosToUpdate(const int targetTerminalIdToFind, const int bigramListPos) const;
int getEntryPosToUpdate(const int targetTerminalIdToFind, const int bigramListPos,
int *const outTailEntryPos) const;
const BigramEntry createUpdatedBigramEntryFrom(const BigramEntry *const originalBigramEntry,
const int newProbability, const int timestamp) const;

View File

@ -88,6 +88,10 @@ class BigramDictContent : public SparseTableDictContent {
const BigramDictContent *const originalBigramDictContent,
int *const outBigramEntryCount);
bool isContentTailPos(const int pos) const {
return pos == getContentBuffer()->getTailPosition();
}
private:
DISALLOW_COPY_AND_ASSIGN(BigramDictContent);