mosesdecoder/lm/value.hh
2012-10-15 13:58:33 +01:00

158 lines
3.8 KiB
C++

#ifndef LM_VALUE__
#define LM_VALUE__
#include "lm/model_type.hh"
#include "lm/value_build.hh"
#include "lm/weights.hh"
#include "util/bit_packing.hh"
#include <stdint.h>
namespace lm {
namespace ngram {
// Template proxy for probing unigrams and middle.
template <class Weights> class GenericProbingProxy {
public:
explicit GenericProbingProxy(const Weights &to) : to_(&to) {}
GenericProbingProxy() : to_(0) {}
bool Found() const { return to_ != 0; }
float Prob() const {
util::FloatEnc enc;
enc.f = to_->prob;
enc.i |= util::kSignBit;
return enc.f;
}
float Backoff() const { return to_->backoff; }
bool IndependentLeft() const {
util::FloatEnc enc;
enc.f = to_->prob;
return enc.i & util::kSignBit;
}
protected:
const Weights *to_;
};
// Basic proxy for trie unigrams.
template <class Weights> class GenericTrieUnigramProxy {
public:
explicit GenericTrieUnigramProxy(const Weights &to) : to_(&to) {}
GenericTrieUnigramProxy() : to_(0) {}
bool Found() const { return to_ != 0; }
float Prob() const { return to_->prob; }
float Backoff() const { return to_->backoff; }
float Rest() const { return Prob(); }
protected:
const Weights *to_;
};
struct BackoffValue {
typedef ProbBackoff Weights;
static const ModelType kProbingModelType = PROBING;
class ProbingProxy : public GenericProbingProxy<Weights> {
public:
explicit ProbingProxy(const Weights &to) : GenericProbingProxy<Weights>(to) {}
ProbingProxy() {}
float Rest() const { return Prob(); }
};
class TrieUnigramProxy : public GenericTrieUnigramProxy<Weights> {
public:
explicit TrieUnigramProxy(const Weights &to) : GenericTrieUnigramProxy<Weights>(to) {}
TrieUnigramProxy() {}
float Rest() const { return Prob(); }
};
struct ProbingEntry {
typedef uint64_t Key;
typedef Weights Value;
uint64_t key;
ProbBackoff value;
uint64_t GetKey() const { return key; }
};
struct TrieUnigramValue {
Weights weights;
uint64_t next;
uint64_t Next() const { return next; }
};
const static bool kDifferentRest = false;
template <class Model, class C> void Callback(const Config &, unsigned int, typename Model::Vocabulary &, C &callback) {
NoRestBuild build;
callback(build);
}
};
struct RestValue {
typedef RestWeights Weights;
static const ModelType kProbingModelType = REST_PROBING;
class ProbingProxy : public GenericProbingProxy<RestWeights> {
public:
explicit ProbingProxy(const Weights &to) : GenericProbingProxy<RestWeights>(to) {}
ProbingProxy() {}
float Rest() const { return to_->rest; }
};
class TrieUnigramProxy : public GenericTrieUnigramProxy<Weights> {
public:
explicit TrieUnigramProxy(const Weights &to) : GenericTrieUnigramProxy<Weights>(to) {}
TrieUnigramProxy() {}
float Rest() const { return to_->rest; }
};
// gcc 4.1 doesn't properly back dependent types :-(.
#pragma pack(push)
#pragma pack(4)
struct ProbingEntry {
typedef uint64_t Key;
typedef Weights Value;
Key key;
Value value;
Key GetKey() const { return key; }
};
struct TrieUnigramValue {
Weights weights;
uint64_t next;
uint64_t Next() const { return next; }
};
#pragma pack(pop)
const static bool kDifferentRest = true;
template <class Model, class C> void Callback(const Config &config, unsigned int order, typename Model::Vocabulary &vocab, C &callback) {
switch (config.rest_function) {
case Config::REST_MAX:
{
MaxRestBuild build;
callback(build);
}
break;
case Config::REST_LOWER:
{
LowerRestBuild<Model> build(config, order, vocab);
callback(build);
}
break;
}
}
};
} // namespace ngram
} // namespace lm
#endif // LM_VALUE__