diff options
author | Avneesh Saluja <asaluja@gmail.com> | 2013-03-28 18:28:16 -0700 |
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committer | Avneesh Saluja <asaluja@gmail.com> | 2013-03-28 18:28:16 -0700 |
commit | 5b8253e0e1f1393a509fb9975ba8c1347af758ed (patch) | |
tree | 1790470b1d07a0b4973ebce19192e896566ea60b /klm/search/dedupe.hh | |
parent | 2389a5a8a43dda87c355579838559515b0428421 (diff) | |
parent | b203f8c5dc8cff1b9c9c2073832b248fcad0765a (diff) |
fixed conflicts
Diffstat (limited to 'klm/search/dedupe.hh')
-rw-r--r-- | klm/search/dedupe.hh | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/klm/search/dedupe.hh b/klm/search/dedupe.hh new file mode 100644 index 00000000..7eaa3b95 --- /dev/null +++ b/klm/search/dedupe.hh @@ -0,0 +1,131 @@ +#ifndef SEARCH_DEDUPE__ +#define SEARCH_DEDUPE__ + +#include "lm/state.hh" +#include "search/edge_generator.hh" + +#include <boost/pool/object_pool.hpp> +#include <boost/unordered_map.hpp> + +namespace search { + +class Dedupe { + public: + Dedupe() {} + + PartialEdge AllocateEdge(Arity arity) { + return behind_.AllocateEdge(arity); + } + + void AddEdge(PartialEdge edge) { + edge.MutableFlags() = 0; + + uint64_t hash = 0; + const PartialVertex *v = edge.NT(); + const PartialVertex *v_end = v + edge.GetArity(); + for (; v != v_end; ++v) { + const void *ptr = v->Identify(); + hash = util::MurmurHashNative(&ptr, sizeof(const void*), hash); + } + + const lm::ngram::ChartState *c = edge.Between(); + const lm::ngram::ChartState *const c_end = c + edge.GetArity() + 1; + for (; c != c_end; ++c) hash = hash_value(*c, hash); + + std::pair<Table::iterator, bool> ret(table_.insert(std::make_pair(hash, edge))); + if (!ret.second) FoundDupe(ret.first->second, edge); + } + + bool Empty() const { return behind_.Empty(); } + + template <class Model, class Output> void Search(Context<Model> &context, Output &output) { + for (Table::const_iterator i(table_.begin()); i != table_.end(); ++i) { + behind_.AddEdge(i->second); + } + Unpack<Output> unpack(output, *this); + behind_.Search(context, unpack); + } + + private: + void FoundDupe(PartialEdge &table, PartialEdge adding) { + if (table.GetFlags() & kPackedFlag) { + Packed &packed = *static_cast<Packed*>(table.GetNote().mut); + if (table.GetScore() >= adding.GetScore()) { + packed.others.push_back(adding); + return; + } + Note original(packed.original); + packed.original = adding.GetNote(); + adding.SetNote(table.GetNote()); + table.SetNote(original); + packed.others.push_back(table); + packed.starting = adding.GetScore(); + table = adding; + table.MutableFlags() |= kPackedFlag; + return; + } + PartialEdge loser; + if (adding.GetScore() > table.GetScore()) { + loser = table; + table = adding; + } else { + loser = adding; + } + // table is winner, loser is loser... + packed_.construct(table, loser); + } + + struct Packed { + Packed(PartialEdge winner, PartialEdge loser) + : original(winner.GetNote()), starting(winner.GetScore()), others(1, loser) { + winner.MutableNote().vp = this; + winner.MutableFlags() |= kPackedFlag; + loser.MutableFlags() &= ~kPackedFlag; + } + Note original; + Score starting; + std::vector<PartialEdge> others; + }; + + template <class Output> class Unpack { + public: + explicit Unpack(Output &output, Dedupe &owner) : output_(output), owner_(owner) {} + + void NewHypothesis(PartialEdge edge) { + if (edge.GetFlags() & kPackedFlag) { + Packed &packed = *reinterpret_cast<Packed*>(edge.GetNote().mut); + edge.SetNote(packed.original); + edge.MutableFlags() = 0; + std::size_t copy_size = sizeof(PartialVertex) * edge.GetArity() + sizeof(lm::ngram::ChartState); + for (std::vector<PartialEdge>::iterator i = packed.others.begin(); i != packed.others.end(); ++i) { + PartialEdge copy(owner_.AllocateEdge(edge.GetArity())); + copy.SetScore(edge.GetScore() - packed.starting + i->GetScore()); + copy.MutableFlags() = 0; + copy.SetNote(i->GetNote()); + memcpy(copy.NT(), edge.NT(), copy_size); + output_.NewHypothesis(copy); + } + } + output_.NewHypothesis(edge); + } + + void FinishedSearch() { + output_.FinishedSearch(); + } + + private: + Output &output_; + Dedupe &owner_; + }; + + EdgeGenerator behind_; + + typedef boost::unordered_map<uint64_t, PartialEdge> Table; + Table table_; + + boost::object_pool<Packed> packed_; + + static const uint16_t kPackedFlag = 1; +}; +} // namespace search +#endif // SEARCH_DEDUPE__ |