Score evaluate_pieces_of_color(const Position& pos, EvalInfo& ei, Score& mobility);
template<Color Us, bool Trace>
- Score evaluate_king(const Position& pos, EvalInfo& ei, Value margins[]);
+ Score evaluate_king(const Position& pos, EvalInfo& ei, int16_t margins[]);
template<Color Us>
Score evaluate_threats(const Position& pos, EvalInfo& ei);
assert(!pos.in_check());
EvalInfo ei;
- Value margins[COLOR_NB];
Score score, mobilityWhite, mobilityBlack;
+ Key key = pos.key();
+ Eval::Entry* e = pos.this_thread()->evalTable[key];
+
+ // If e->key matches the position's hash key, it means that we have analysed
+ // this node before, and we can simply return the information we found the last
+ // time instead of recomputing it.
+ if (e->key == key)
+ {
+ margin = Value(e->margins[pos.side_to_move()]);
+ return e->value;
+ }
+
+ // Otherwise we overwrite current content with this node info.
+ e->key = key;
+
// margins[] store the uncertainty estimation of position's evaluation
// that typically is used by the search for pruning decisions.
- margins[WHITE] = margins[BLACK] = VALUE_ZERO;
+ e->margins[WHITE] = e->margins[BLACK] = VALUE_ZERO;
// Initialize score by reading the incrementally updated scores included
// in the position object (material + piece square tables) and adding
if (ei.mi->specialized_eval_exists())
{
margin = VALUE_ZERO;
- return ei.mi->evaluate(pos);
+ e->value = ei.mi->evaluate(pos);
+ return e->value;
}
// Probe the pawn hash table
// Evaluate kings after all other pieces because we need complete attack
// information when computing the king safety evaluation.
- score += evaluate_king<WHITE, Trace>(pos, ei, margins)
- - evaluate_king<BLACK, Trace>(pos, ei, margins);
+ score += evaluate_king<WHITE, Trace>(pos, ei, e->margins)
+ - evaluate_king<BLACK, Trace>(pos, ei, e->margins);
// Evaluate tactical threats, we need full attack information including king
score += evaluate_threats<WHITE>(pos, ei)
sf = ScaleFactor(50);
}
- margin = margins[pos.side_to_move()];
+ margin = Value(e->margins[pos.side_to_move()]);
Value v = interpolate(score, ei.mi->game_phase(), sf);
// In case of tracing add all single evaluation contributions for both white and black
Score b = make_score(ei.mi->space_weight() * evaluate_space<BLACK>(pos, ei), 0);
trace_add(SPACE, apply_weight(w, Weights[Space]), apply_weight(b, Weights[Space]));
trace_add(TOTAL, score);
- TraceStream << "\nUncertainty margin: White: " << to_cp(margins[WHITE])
- << ", Black: " << to_cp(margins[BLACK])
+ TraceStream << "\nUncertainty margin: White: " << to_cp(Value(e->margins[WHITE]))
+ << ", Black: " << to_cp(Value(e->margins[BLACK]))
<< "\nScaling: " << std::noshowpos
<< std::setw(6) << 100.0 * ei.mi->game_phase() / 128.0 << "% MG, "
<< std::setw(6) << 100.0 * (1.0 - ei.mi->game_phase() / 128.0) << "% * "
<< "Total evaluation: " << to_cp(v);
}
- return pos.side_to_move() == WHITE ? v : -v;
+ return e->value = pos.side_to_move() == WHITE ? v : -v;
}
// evaluate_king<>() assigns bonuses and penalties to a king of a given color
template<Color Us, bool Trace>
- Score evaluate_king(const Position& pos, EvalInfo& ei, Value margins[]) {
+ Score evaluate_king(const Position& pos, EvalInfo& ei, int16_t margins[]) {
const Color Them = (Us == WHITE ? BLACK : WHITE);
// be very big, and so capturing a single attacking piece can therefore
// result in a score change far bigger than the value of the captured piece.
score -= KingDangerTable[Us == Search::RootColor][attackUnits];
- margins[Us] += mg_value(KingDangerTable[Us == Search::RootColor][attackUnits]);
+ margins[Us] += int16_t(mg_value(KingDangerTable[Us == Search::RootColor][attackUnits]));
}
if (Trace)