+++ /dev/null
-/*
- Stockfish, a UCI chess playing engine derived from Glaurung 2.1
- Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
-
- Stockfish is free software: you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation, either version 3 of the License, or
- (at your option) any later version.
-
- Stockfish is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with this program. If not, see <http://www.gnu.org/licenses/>.
-*/
-
-// A class template that represents the input feature set of the NNUE evaluation function
-
-#ifndef NNUE_FEATURE_SET_H_INCLUDED
-#define NNUE_FEATURE_SET_H_INCLUDED
-
-#include "features_common.h"
-#include <array>
-
-namespace Eval::NNUE::Features {
-
- // Class template that represents a list of values
- template <typename T, T... Values>
- struct CompileTimeList;
-
- template <typename T, T First, T... Remaining>
- struct CompileTimeList<T, First, Remaining...> {
- static constexpr bool Contains(T value) {
- return value == First || CompileTimeList<T, Remaining...>::Contains(value);
- }
- static constexpr std::array<T, sizeof...(Remaining) + 1>
- kValues = {{First, Remaining...}};
- };
-
- // Base class of feature set
- template <typename Derived>
- class FeatureSetBase {
-
- public:
- // Get a list of indices for active features
- template <typename IndexListType>
- static void AppendActiveIndices(
- const Position& pos, TriggerEvent trigger, IndexListType active[2]) {
-
- for (Color perspective : { WHITE, BLACK }) {
- Derived::CollectActiveIndices(
- pos, trigger, perspective, &active[perspective]);
- }
- }
-
- // Get a list of indices for recently changed features
- template <typename PositionType, typename IndexListType>
- static void AppendChangedIndices(
- const PositionType& pos, TriggerEvent trigger,
- IndexListType removed[2], IndexListType added[2], bool reset[2]) {
-
- const auto& dp = pos.state()->dirtyPiece;
- if (dp.dirty_num == 0) return;
-
- for (Color perspective : { WHITE, BLACK }) {
- reset[perspective] = false;
- switch (trigger) {
- case TriggerEvent::kFriendKingMoved:
- reset[perspective] = dp.piece[0] == make_piece(perspective, KING);
- break;
- default:
- assert(false);
- break;
- }
- if (reset[perspective]) {
- Derived::CollectActiveIndices(
- pos, trigger, perspective, &added[perspective]);
- } else {
- Derived::CollectChangedIndices(
- pos, trigger, perspective,
- &removed[perspective], &added[perspective]);
- }
- }
- }
- };
-
- // Class template that represents the feature set
- template <typename FeatureType>
- class FeatureSet<FeatureType> : public FeatureSetBase<FeatureSet<FeatureType>> {
-
- public:
- // Hash value embedded in the evaluation file
- static constexpr std::uint32_t kHashValue = FeatureType::kHashValue;
- // Number of feature dimensions
- static constexpr IndexType kDimensions = FeatureType::kDimensions;
- // Maximum number of simultaneously active features
- static constexpr IndexType kMaxActiveDimensions =
- FeatureType::kMaxActiveDimensions;
- // Trigger for full calculation instead of difference calculation
- using SortedTriggerSet =
- CompileTimeList<TriggerEvent, FeatureType::kRefreshTrigger>;
- static constexpr auto kRefreshTriggers = SortedTriggerSet::kValues;
-
- private:
- // Get a list of indices for active features
- static void CollectActiveIndices(
- const Position& pos, const TriggerEvent trigger, const Color perspective,
- IndexList* const active) {
- if (FeatureType::kRefreshTrigger == trigger) {
- FeatureType::AppendActiveIndices(pos, perspective, active);
- }
- }
-
- // Get a list of indices for recently changed features
- static void CollectChangedIndices(
- const Position& pos, const TriggerEvent trigger, const Color perspective,
- IndexList* const removed, IndexList* const added) {
-
- if (FeatureType::kRefreshTrigger == trigger) {
- FeatureType::AppendChangedIndices(pos, perspective, removed, added);
- }
- }
-
- // Make the base class and the class template that recursively uses itself a friend
- friend class FeatureSetBase<FeatureSet>;
- template <typename... FeatureTypes>
- friend class FeatureSet;
- };
-
-} // namespace Eval::NNUE::Features
-
-#endif // #ifndef NNUE_FEATURE_SET_H_INCLUDED