mosesdecoder/moses2/TranslationModel/ProbingPT.cpp

/*
 * ProbingPT.cpp
 *
 *  Created on: 3 Nov 2015
 *      Author: hieu
 */
#include <boost/foreach.hpp>
#include "ProbingPT.h"
#include "probingpt/querying.h"
#include "probingpt/probing_hash_utils.h"
#include "util/exception.hh"
#include "../System.h"
#include "../Scores.h"
#include "../Phrase.h"
#include "../legacy/InputFileStream.h"
#include "../legacy/FactorCollection.h"
#include "../legacy/Util2.h"
#include "../FF/FeatureFunctions.h"
#include "../PhraseBased/PhraseImpl.h"
#include "../PhraseBased/TargetPhraseImpl.h"
#include "../PhraseBased/Manager.h"
#include "../PhraseBased/TargetPhrases.h"
#include "../SCFG/InputPath.h"
#include "../SCFG/Manager.h"
#include "../SCFG/TargetPhraseImpl.h"
#include "../SCFG/PhraseImpl.h"

using namespace std;

namespace Moses2
{
ProbingPT::ActiveChartEntryProbing::ActiveChartEntryProbing(
  MemPool &pool,
  const ActiveChartEntryProbing &prevEntry)
  :Parent(prevEntry)
  ,m_key(prevEntry.m_key)
{}

void ProbingPT::ActiveChartEntryProbing::AddSymbolBindElement(
  const Range &range,
  const SCFG::Word &word,
  const Moses2::Hypotheses *hypos,
  const Moses2::PhraseTable &pt)
{
  const ProbingPT &probingPt = static_cast<const ProbingPT&>(pt);
  std::pair<bool, uint64_t> key = GetKey(word, probingPt);
  UTIL_THROW_IF2(!key.first, "Word should have been in source vocab");
  m_key = key.second;

  ActiveChartEntry::AddSymbolBindElement(range, word, hypos, pt);
}

std::pair<bool, uint64_t> ProbingPT::ActiveChartEntryProbing::GetKey(const SCFG::Word &nextWord, const ProbingPT &pt) const
{
  std::pair<bool, uint64_t> ret;
  ret.second = m_key;
  uint64_t probingId = pt.GetSourceProbingId(nextWord);
  if (probingId == pt.GetUnk()) {
    ret.first = false;
    return ret;
  }

  ret.first = true;
  size_t phraseSize = m_symbolBind.coll.size();
  ret.second += probingId << phraseSize;
  return ret;
}

////////////////////////////////////////////////////////////////////////////
ProbingPT::ProbingPT(size_t startInd, const std::string &line)
  :PhraseTable(startInd, line)
  ,load_method(util::POPULATE_OR_READ)
{
  ReadParameters();
}

ProbingPT::~ProbingPT()
{
  delete m_engine;
}

void ProbingPT::Load(System &system)
{
  m_engine = new probingpt::QueryEngine(m_path.c_str(), load_method);

  m_unkId = 456456546456;

  FactorCollection &vocab = system.GetVocab();

  // source vocab
  const std::map<uint64_t, std::string> &sourceVocab =
    m_engine->getSourceVocab();
  std::map<uint64_t, std::string>::const_iterator iterSource;
  for (iterSource = sourceVocab.begin(); iterSource != sourceVocab.end();
       ++iterSource) {
    string wordStr = iterSource->second;
    bool isNT;
    //cerr << "wordStr=" << wordStr << endl;
    ReformatWord(system, wordStr, isNT);
    //cerr << "wordStr=" << wordStr << endl;

    const Factor *factor = vocab.AddFactor(wordStr, system, isNT);

    uint64_t probingId = iterSource->first;
    size_t factorId = factor->GetId();

    if (factorId >= m_sourceVocab.size()) {
      m_sourceVocab.resize(factorId + 1, m_unkId);
    }
    m_sourceVocab[factorId] = probingId;
  }

  // target vocab
  InputFileStream targetVocabStrme(m_path + "/TargetVocab.dat");
  string line;
  while (getline(targetVocabStrme, line)) {
    vector<string> toks = Tokenize(line, "\t");
    UTIL_THROW_IF2(toks.size() != 2, string("Incorrect format:") + line + "\n");

    bool isNT;
    //cerr << "wordStr=" << toks[0] << endl;
    ReformatWord(system, toks[0], isNT);
    //cerr << "wordStr=" << toks[0] << endl;

    const Factor *factor = vocab.AddFactor(toks[0], system, isNT);
    uint32_t probingId = Scan<uint32_t>(toks[1]);

    if (probingId >= m_targetVocab.size()) {
      m_targetVocab.resize(probingId + 1);
    }

    std::pair<bool, const Factor*> ele(isNT, factor);
    m_targetVocab[probingId] = ele;
  }

  // alignments
  CreateAlignmentMap(system, m_path + "/Alignments.dat");

  // cache
  CreateCache(system);
}

void ProbingPT::SetParameter(const std::string& key, const std::string& value)
{
  if (key == "load") {
    if (value == "lazy") {
      load_method = util::LAZY;
    } else if (value == "populate_or_lazy") {
      load_method = util::POPULATE_OR_LAZY;
    } else if (value == "populate_or_read" || value == "populate") {
      load_method = util::POPULATE_OR_READ;
    } else if (value == "read") {
      load_method = util::READ;
    } else if (value == "parallel_read") {
      load_method = util::PARALLEL_READ;
    } else {
      UTIL_THROW2("load method not supported" << value);
    }
  } else {
    PhraseTable::SetParameter(key, value);
  }
}

void ProbingPT::CreateAlignmentMap(System &system, const std::string path)
{
  const std::vector< std::vector<unsigned char> > &probingAlignColl = m_engine->getAlignments();
  m_aligns.resize(probingAlignColl.size(), NULL);

  for (size_t i = 0; i < probingAlignColl.size(); ++i) {
    AlignmentInfo::CollType aligns;

    const std::vector<unsigned char> &probingAligns = probingAlignColl[i];
    for (size_t j = 0; j < probingAligns.size(); j += 2) {
      size_t startPos = probingAligns[j];
      size_t endPos = probingAligns[j+1];
      //cerr << "startPos=" << startPos << " " << endPos << endl;
      aligns.insert(std::pair<size_t,size_t>(startPos, endPos));
    }

    const AlignmentInfo *align = AlignmentInfoCollection::Instance().Add(aligns);
    m_aligns[i] = align;
    //cerr << "align=" << align->Debug(system) << endl;
  }
}

void ProbingPT::Lookup(const Manager &mgr, InputPathsBase &inputPaths) const
{
  BOOST_FOREACH(InputPathBase *pathBase, inputPaths) {
    InputPath *path = static_cast<InputPath*>(pathBase);

    if (SatisfyBackoff(mgr, *path)) {
      TargetPhrases *tpsPtr;
      tpsPtr = Lookup(mgr, mgr.GetPool(), *path);
      path->AddTargetPhrases(*this, tpsPtr);
    }
  }
}

TargetPhrases* ProbingPT::Lookup(const Manager &mgr, MemPool &pool,
                                 InputPath &inputPath) const
{
  /*
   if (inputPath.prefixPath && inputPath.prefixPath->GetTargetPhrases(*this) == NULL) {
   // assume all paths have prefixes, except rules with 1 word source
   return NULL;
   }
   else {
   const Phrase &sourcePhrase = inputPath.subPhrase;
   std::pair<TargetPhrases*, uint64_t> tpsAndKey = CreateTargetPhrase(pool, mgr.system, sourcePhrase);
   return tpsAndKey.first;
   }
   */
  const Phrase<Moses2::Word> &sourcePhrase = inputPath.subPhrase;

  // get hash for source phrase
  std::pair<bool, uint64_t> keyStruct = GetKey(sourcePhrase);
  if (!keyStruct.first) {
    return NULL;
  }

  // check in cache
  CachePb::const_iterator iter = m_cachePb.find(keyStruct.second);
  if (iter != m_cachePb.end()) {
    //cerr << "FOUND IN CACHE " << keyStruct.second << " " << sourcePhrase.Debug(mgr.system) << endl;
    TargetPhrases *tps = iter->second;
    return tps;
  }

  // query pt
  TargetPhrases *tps = CreateTargetPhrases(pool, mgr.system, sourcePhrase,
                       keyStruct.second);
  return tps;
}

std::pair<bool, uint64_t> ProbingPT::GetKey(const Phrase<Moses2::Word> &sourcePhrase) const
{
  std::pair<bool, uint64_t> ret;

  // create a target phrase from the 1st word of the source, prefix with 'ProbingPT:'
  size_t sourceSize = sourcePhrase.GetSize();
  assert(sourceSize);

  uint64_t *probingSource = (uint64_t*) alloca(sourceSize * sizeof(uint64_t));
  GetSourceProbingIds(sourcePhrase, ret.first, probingSource);
  if (!ret.first) {
    // source phrase contains a word unknown in the pt.
    // We know immediately there's no translation for it
  } else {
    ret.second = m_engine->getKey(probingSource, sourceSize);
  }

  return ret;

}

TargetPhrases *ProbingPT::CreateTargetPhrases(MemPool &pool,
    const System &system, const Phrase<Moses2::Word> &sourcePhrase, uint64_t key) const
{
  TargetPhrases *tps = NULL;

  //Actual lookup
  std::pair<bool, uint64_t> query_result; // 1st=found, 2nd=target file offset
  query_result = m_engine->query(key);
  //cerr << "key2=" << query_result.second << endl;

  if (query_result.first) {
    const char *offset = m_engine->memTPS + query_result.second;
    uint64_t *numTP = (uint64_t*) offset;

    tps = new (pool.Allocate<TargetPhrases>()) TargetPhrases(pool, *numTP);

    offset += sizeof(uint64_t);
    for (size_t i = 0; i < *numTP; ++i) {
      TargetPhraseImpl *tp = CreateTargetPhrase(pool, system, offset);
      assert(tp);
      const FeatureFunctions &ffs = system.featureFunctions;
      ffs.EvaluateInIsolation(pool, system, sourcePhrase, *tp);

      tps->AddTargetPhrase(*tp);

    }

    tps->SortAndPrune(m_tableLimit);
    system.featureFunctions.EvaluateAfterTablePruning(pool, *tps, sourcePhrase);
    //cerr << *tps << endl;
  }

  return tps;
}

TargetPhraseImpl *ProbingPT::CreateTargetPhrase(
  MemPool &pool,
  const System &system,
  const char *&offset) const
{
  probingpt::TargetPhraseInfo *tpInfo = (probingpt::TargetPhraseInfo*) offset;
  size_t numRealWords = tpInfo->numWords / m_output.size();

  TargetPhraseImpl *tp =
    new (pool.Allocate<TargetPhraseImpl>()) TargetPhraseImpl(pool, *this,
        system, numRealWords);

  offset += sizeof(probingpt::TargetPhraseInfo);

  // scores
  SCORE *scores = (SCORE*) offset;

  size_t totalNumScores = m_engine->num_scores + m_engine->num_lex_scores;

  if (m_engine->logProb) {
    // set pt score for rule
    tp->GetScores().PlusEquals(system, *this, scores);

    // save scores for other FF, eg. lex RO. Just give the offset
    if (m_engine->num_lex_scores) {
      tp->scoreProperties = scores + m_engine->num_scores;
    }
  } else {
    // log score 1st
    SCORE *logScores = (SCORE*) alloca(totalNumScores * sizeof(SCORE));
    for (size_t i = 0; i < totalNumScores; ++i) {
      logScores[i] = FloorScore(TransformScore(scores[i]));
    }

    // set pt score for rule
    tp->GetScores().PlusEquals(system, *this, logScores);

    // save scores for other FF, eg. lex RO.
    tp->scoreProperties = pool.Allocate<SCORE>(m_engine->num_lex_scores);
    for (size_t i = 0; i < m_engine->num_lex_scores; ++i) {
      tp->scoreProperties[i] = logScores[i + m_engine->num_scores];
    }
  }

  offset += sizeof(SCORE) * totalNumScores;

  // words
  for (size_t targetPos = 0; targetPos < numRealWords; ++targetPos) {
    for (size_t i = 0; i < m_output.size(); ++i) {
      FactorType factorType = m_output[i];

      uint32_t *probingId = (uint32_t*) offset;

      const std::pair<bool, const Factor *> *factorPair = GetTargetFactor(*probingId);
      assert(factorPair);
      assert(!factorPair->first);

      Word &word = (*tp)[targetPos];
      word[factorType] = factorPair->second;

      offset += sizeof(uint32_t);
    }
  }

  // align
  uint32_t alignTerm = tpInfo->alignTerm;
  //cerr << "alignTerm=" << alignTerm << endl;
  UTIL_THROW_IF2(alignTerm >= m_aligns.size(), "Unknown alignInd");
  tp->Parent::SetAlignTerm(*m_aligns[alignTerm]);

  // properties TODO

  return tp;
}

void ProbingPT::GetSourceProbingIds(const Phrase<Moses2::Word> &sourcePhrase,
                                    bool &ok, uint64_t probingSource[]) const
{

  size_t size = sourcePhrase.GetSize();
  for (size_t i = 0; i < size; ++i) {
    const Word &word = sourcePhrase[i];
    uint64_t probingId = GetSourceProbingId(word);
    if (probingId == m_unkId) {
      ok = false;
      return;
    } else {
      probingSource[i] = probingId;
    }
  }

  ok = true;
}

uint64_t ProbingPT::GetSourceProbingId(const Word &word) const
{
  uint64_t ret = 0;

  for (size_t i = 0; i < m_input.size(); ++i) {
    FactorType factorType = m_input[i];
    const Factor *factor = word[factorType];

    size_t factorId = factor->GetId();
    if (factorId >= m_sourceVocab.size()) {
      return m_unkId;
    }
    ret += m_sourceVocab[factorId];
  }

  return ret;
}

void ProbingPT::CreateCache(System &system)
{
  if (m_maxCacheSize == 0) {
    return;
  }

  string filePath = m_path + "/cache";
  InputFileStream strme(filePath);

  string line;
  getline(strme, line);
  //float totalCount = Scan<float>(line);

  MemPool &pool = system.GetSystemPool();
  FactorCollection &vocab = system.GetVocab();

  MemPool tmpSourcePool;

  size_t lineCount = 0;
  while (getline(strme, line) && lineCount < m_maxCacheSize) {
    vector<string> toks = Tokenize(line, "\t");
    assert(toks.size() == 3);
    uint64_t key = Scan<uint64_t>(toks[1]);
    //cerr << "line=" << line << endl;

    if (system.isPb) {
      PhraseImpl *sourcePhrase = PhraseImpl::CreateFromString(tmpSourcePool, vocab, system, toks[2]);

      /*
      std::pair<bool, uint64_t> retStruct = GetKey(*sourcePhrase);
      if (!retStruct.first) {
      UTIL_THROW2("Unknown cache entry");
      }
      cerr << "key=" << retStruct.second << " " << key << endl;
      */
      TargetPhrases *tps = CreateTargetPhrases(pool, system, *sourcePhrase, key);
      assert(tps);

      m_cachePb[key] = tps;
    } else {
      // SCFG
      SCFG::PhraseImpl *sourcePhrase = SCFG::PhraseImpl::CreateFromString(tmpSourcePool, vocab, system, toks[2], false);
      //cerr << "sourcePhrase=" << sourcePhrase->Debug(system) << endl;

      std::pair<bool, SCFG::TargetPhrases*> tpsPair = CreateTargetPhrasesSCFG(pool, system, *sourcePhrase, key);
      assert(tpsPair.first && tpsPair.second);

      m_cacheSCFG[key] = tpsPair.second;
    }
    ++lineCount;
  }

}

///////////////////////////////////////////////////////////////////////////////
// SCFG
///////////////////////////////////////////////////////////////////////////////

void ProbingPT::ReformatWord(System &system, std::string &wordStr, bool &isNT)
{
  isNT = false;
  if (system.isPb) {
    return;
  } else {
    isNT = (wordStr[0] == '[' && wordStr[wordStr.size() - 1] == ']');
    //cerr << "nt=" << nt << endl;

    if (isNT) {
      size_t startPos = wordStr.find("][");
      if (startPos == string::npos) {
        startPos = 1;
      } else {
        startPos += 2;
      }

      wordStr = wordStr.substr(startPos, wordStr.size() - startPos - 1);
      //cerr << "wordStr=" << wordStr << endl;
    }
  }
}

void ProbingPT::InitActiveChart(
  MemPool &pool,
  const SCFG::Manager &mgr,
  SCFG::InputPath &path) const
{
  //cerr << "InitActiveChart=" << path.Debug(cerr, mgr.system) << endl;
  size_t ptInd = GetPtInd();
  ActiveChartEntryProbing *chartEntry = new (pool.Allocate<ActiveChartEntryProbing>()) ActiveChartEntryProbing(pool);
  path.AddActiveChartEntry(ptInd, chartEntry);
}

void ProbingPT::Lookup(MemPool &pool,
                       const SCFG::Manager &mgr,
                       size_t maxChartSpan,
                       const SCFG::Stacks &stacks,
                       SCFG::InputPath &path) const
{
  //cerr << "Lookup=" << endl;
  if (path.range.GetNumWordsCovered() > maxChartSpan) {
    return;
  }

  size_t endPos = path.range.GetEndPos();

  const SCFG::InputPath *prevPath = static_cast<const SCFG::InputPath*>(path.prefixPath);
  UTIL_THROW_IF2(prevPath == NULL, "prefixPath == NULL");

  // TERMINAL
  const SCFG::Word &lastWord = path.subPhrase.Back();

  const SCFG::InputPath &subPhrasePath = *mgr.GetInputPaths().GetMatrix().GetValue(endPos, 1);

  //cerr << "BEFORE LookupGivenWord=" << *prevPath << endl;
  LookupGivenWord(pool, mgr, *prevPath, lastWord, NULL, subPhrasePath.range, path);
  //cerr << "AFTER LookupGivenWord=" << *prevPath << endl;

  // NON-TERMINAL
  //const SCFG::InputPath *prefixPath = static_cast<const SCFG::InputPath*>(path.prefixPath);
  while (prevPath) {
    const Range &prevRange = prevPath->range;
    //cerr << "prevRange=" << prevRange << endl;

    size_t startPos = prevRange.GetEndPos() + 1;
    size_t ntSize = endPos - startPos + 1;
    const SCFG::InputPath &subPhrasePath = *mgr.GetInputPaths().GetMatrix().GetValue(startPos, ntSize);

    LookupNT(pool, mgr, subPhrasePath.range, *prevPath, stacks, path);

    prevPath = static_cast<const SCFG::InputPath*>(prevPath->prefixPath);
  }
}

void ProbingPT::LookupGivenNode(
  MemPool &pool,
  const SCFG::Manager &mgr,
  const SCFG::ActiveChartEntry &prevEntry,
  const SCFG::Word &wordSought,
  const Moses2::Hypotheses *hypos,
  const Moses2::Range &subPhraseRange,
  SCFG::InputPath &outPath) const
{
  const ActiveChartEntryProbing &prevEntryCast = static_cast<const ActiveChartEntryProbing&>(prevEntry);

  std::pair<bool, uint64_t> key = prevEntryCast.GetKey(wordSought, *this);

  if (!key.first) {
    // should only occasionally happen when looking up unary rules
    return;
  }

  const Phrase<SCFG::Word> &sourcePhrase = outPath.subPhrase;

  // check in cache
  CacheSCFG::const_iterator iter = m_cacheSCFG.find(key.second);
  if (iter != m_cacheSCFG.end()) {
    //cerr << "FOUND IN CACHE " << key.second << " " << sourcePhrase.Debug(mgr.system) << endl;
    SCFG::TargetPhrases *tps = iter->second;

    ActiveChartEntryProbing *chartEntry = new (pool.Allocate<ActiveChartEntryProbing>()) ActiveChartEntryProbing(pool, prevEntryCast);
    //cerr << "AFTER chartEntry" << endl;

    chartEntry->AddSymbolBindElement(subPhraseRange, wordSought, hypos, *this);
    //cerr << "AFTER AddSymbolBindElement" << endl;

    size_t ptInd = GetPtInd();
    outPath.AddActiveChartEntry(ptInd, chartEntry);

    outPath.AddTargetPhrasesToPath(pool, mgr.system, *this, *tps, chartEntry->GetSymbolBind());
  } else {
    // not in cache. Lookup
    std::pair<bool, SCFG::TargetPhrases*> tpsPair = CreateTargetPhrasesSCFG(pool, mgr.system, sourcePhrase, key.second);
    assert(tpsPair.first && tpsPair.second);

    if (tpsPair.first) {
      // new entries
      ActiveChartEntryProbing *chartEntry = new (pool.Allocate<ActiveChartEntryProbing>()) ActiveChartEntryProbing(pool, prevEntryCast);
      //cerr << "AFTER chartEntry" << endl;

      chartEntry->AddSymbolBindElement(subPhraseRange, wordSought, hypos, *this);
      //cerr << "AFTER AddSymbolBindElement" << endl;

      size_t ptInd = GetPtInd();
      outPath.AddActiveChartEntry(ptInd, chartEntry);
      //cerr << "AFTER AddActiveChartEntry" << endl;

      if (tpsPair.second) {
        // there are some rules
        //cerr << "symbolbind=" << chartEntry->GetSymbolBind().Debug(mgr.system) << endl;
        outPath.AddTargetPhrasesToPath(pool, mgr.system, *this, *tpsPair.second, chartEntry->GetSymbolBind());
      }
    }
  }
}

SCFG::TargetPhraseImpl *ProbingPT::CreateTargetPhraseSCFG(
  MemPool &pool,
  const System &system,
  const char *&offset) const
{
  probingpt::TargetPhraseInfo *tpInfo = (probingpt::TargetPhraseInfo*) offset;
  SCFG::TargetPhraseImpl *tp =
    new (pool.Allocate<SCFG::TargetPhraseImpl>()) SCFG::TargetPhraseImpl(pool, *this,
        system, tpInfo->numWords - 1);

  offset += sizeof(probingpt::TargetPhraseInfo);

  // scores
  SCORE *scores = (SCORE*) offset;

  size_t totalNumScores = m_engine->num_scores + m_engine->num_lex_scores;

  if (m_engine->logProb) {
    // set pt score for rule
    tp->GetScores().PlusEquals(system, *this, scores);

    // save scores for other FF, eg. lex RO. Just give the offset
    if (m_engine->num_lex_scores) {
      tp->scoreProperties = scores + m_engine->num_scores;
    }
  } else {
    // log score 1st
    SCORE *logScores = (SCORE*) alloca(totalNumScores * sizeof(SCORE));
    for (size_t i = 0; i < totalNumScores; ++i) {
      logScores[i] = FloorScore(TransformScore(scores[i]));
    }

    // set pt score for rule
    tp->GetScores().PlusEquals(system, *this, logScores);

    // save scores for other FF, eg. lex RO.
    tp->scoreProperties = pool.Allocate<SCORE>(m_engine->num_lex_scores);
    for (size_t i = 0; i < m_engine->num_lex_scores; ++i) {
      tp->scoreProperties[i] = logScores[i + m_engine->num_scores];
    }
  }

  offset += sizeof(SCORE) * totalNumScores;

  // words
  for (size_t i = 0; i < tpInfo->numWords - 1; ++i) {
    uint32_t *probingId = (uint32_t*) offset;

    const std::pair<bool, const Factor *> *factorPair = GetTargetFactor(*probingId);
    assert(factorPair);

    SCFG::Word &word = (*tp)[i];
    word[0] = factorPair->second;
    word.isNonTerminal = factorPair->first;

    offset += sizeof(uint32_t);
  }

  // lhs
  uint32_t *probingId = (uint32_t*) offset;

  const std::pair<bool, const Factor *> *factorPair = GetTargetFactor(*probingId);
  assert(factorPair);
  assert(factorPair->first);

  tp->lhs[0] = factorPair->second;
  tp->lhs.isNonTerminal = factorPair->first;

  offset += sizeof(uint32_t);

  // align
  uint32_t alignTerm = tpInfo->alignTerm;
  //cerr << "alignTerm=" << alignTerm << endl;
  UTIL_THROW_IF2(alignTerm >= m_aligns.size(), "Unknown alignInd");
  tp->Parent::SetAlignTerm(*m_aligns[alignTerm]);

  uint32_t alignNonTerm = tpInfo->alignNonTerm;
  //cerr << "alignTerm=" << alignTerm << endl;
  UTIL_THROW_IF2(alignNonTerm >= m_aligns.size(), "Unknown alignInd");
  tp->SetAlignNonTerm(*m_aligns[alignNonTerm]);

  // properties TODO

  return tp;
}

std::pair<bool, SCFG::TargetPhrases*> ProbingPT::CreateTargetPhrasesSCFG(MemPool &pool, const System &system,
    const Phrase<SCFG::Word> &sourcePhrase, uint64_t key) const
{
  std::pair<bool, SCFG::TargetPhrases*> ret(false, NULL);

  std::pair<bool, uint64_t> query_result; // 1st=found, 2nd=target file offset
  query_result = m_engine->query(key);
  //cerr << "query_result=" << query_result.first << endl;

  /*
  if (outPath.range.GetStartPos() == 1 || outPath.range.GetStartPos() == 2) {
  cerr  << "range=" << outPath.range
  	  << " prevEntry=" << prevEntry.GetSymbolBind().Debug(mgr.system) << " " << prevEntryCast.GetKey()
  	  << " wordSought=" << wordSought.Debug(mgr.system)
  	  << " key=" << key.first << " " << key.second
  	  << " query_result=" << query_result.first << " " << (query_result.second == NONE)
  	  << endl;
  }
  */

  if (query_result.first) {
    ret.first = true;
    size_t ptInd = GetPtInd();

    if (query_result.second != NONE) {
      // there are some rules
      const FeatureFunctions &ffs = system.featureFunctions;

      const char *offset = m_engine->memTPS + query_result.second;
      uint64_t *numTP = (uint64_t*) offset;
      //cerr << "numTP=" << *numTP << endl;

      SCFG::TargetPhrases *tps = new (pool.Allocate<SCFG::TargetPhrases>()) SCFG::TargetPhrases(pool, *numTP);
      ret.second = tps;

      offset += sizeof(uint64_t);
      for (size_t i = 0; i < *numTP; ++i) {
        SCFG::TargetPhraseImpl *tp = CreateTargetPhraseSCFG(pool, system, offset);
        assert(tp);
        //cerr << "tp=" << tp->Debug(mgr.system) << endl;

        ffs.EvaluateInIsolation(pool, system, sourcePhrase, *tp);

        tps->AddTargetPhrase(*tp);

      }

      tps->SortAndPrune(m_tableLimit);
      ffs.EvaluateAfterTablePruning(pool, *tps, sourcePhrase);
      //cerr << "tps=" << tps->GetSize() << endl;

    }
  }

  return ret;
}

} // namespace