Update to Stockfish 13

DroidFishApp/src/main/cpp/stockfish/benchmark.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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

DroidFishApp/src/main/cpp/stockfish/bitbase.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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

DroidFishApp/src/main/cpp/stockfish/bitboard.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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

DroidFishApp/src/main/cpp/stockfish/bitboard.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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

DroidFishApp/src/main/cpp/stockfish/endgame.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -553,8 +553,8 @@ ScaleFactor Endgame<KRPPKRP>::operator()(const Position& pos) const {
   assert(verify_material(pos, strongSide, RookValueMg, 2));
   assert(verify_material(pos, weakSide,   RookValueMg, 1));
 
-  Square strongPawn1 = pos.squares<PAWN>(strongSide)[0];
+  Square strongPawn1 = lsb(pos.pieces(strongSide, PAWN));
-  Square strongPawn2 = pos.squares<PAWN>(strongSide)[1];
+  Square strongPawn2 = msb(pos.pieces(strongSide, PAWN));
   Square weakKing = pos.square<KING>(weakSide);
 
   // Does the stronger side have a passed pawn?
@@ -638,8 +638,8 @@ ScaleFactor Endgame<KBPPKB>::operator()(const Position& pos) const {
       return SCALE_FACTOR_NONE;
 
   Square weakKing = pos.square<KING>(weakSide);
-  Square strongPawn1 = pos.squares<PAWN>(strongSide)[0];
+  Square strongPawn1 = lsb(pos.pieces(strongSide, PAWN));
-  Square strongPawn2 = pos.squares<PAWN>(strongSide)[1];
+  Square strongPawn2 = msb(pos.pieces(strongSide, PAWN));
   Square blockSq1, blockSq2;
 
   if (relative_rank(strongSide, strongPawn1) > relative_rank(strongSide, strongPawn2))

DroidFishApp/src/main/cpp/stockfish/endgame.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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

DroidFishApp/src/main/cpp/stockfish/evaluate.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -37,12 +37,13 @@
 #include "incbin/incbin.h"
 
 
-// Macro to embed the default NNUE file data in the engine binary (using incbin.h, by Dale Weiler).
+// Macro to embed the default efficiently updatable neural network (NNUE) file
+// data in the engine binary (using incbin.h, by Dale Weiler).
 // This macro invocation will declare the following three variables
 //     const unsigned char        gEmbeddedNNUEData[];  // a pointer to the embedded data
 //     const unsigned char *const gEmbeddedNNUEEnd;     // a marker to the end
 //     const unsigned int         gEmbeddedNNUESize;    // the size of the embedded file
-// Note that this does not work in Microsof Visual Studio.
+// Note that this does not work in Microsoft Visual Studio.
 #if !defined(_MSC_VER) && !defined(NNUE_EMBEDDING_OFF)
   INCBIN(EmbeddedNNUE, EvalFileDefaultName);
 #else
@@ -60,9 +61,9 @@ namespace Eval {
   bool useNNUE;
   string eval_file_loaded = "None";
 
-  /// NNUE::init() tries to load a nnue network at startup time, or when the engine
+  /// NNUE::init() tries to load a NNUE network at startup time, or when the engine
   /// receives a UCI command "setoption name EvalFile value nn-[a-z0-9]{12}.nnue"
-  /// The name of the nnue network is always retrieved from the EvalFile option.
+  /// The name of the NNUE network is always retrieved from the EvalFile option.
   /// We search the given network in three locations: internally (the default
   /// network may be embedded in the binary), in the active working directory and
   /// in the engine directory. Distro packagers may define the DEFAULT_NNUE_DIRECTORY
@@ -187,11 +188,11 @@ using namespace Trace;
 namespace {
 
   // Threshold for lazy and space evaluation
-  constexpr Value LazyThreshold1 =  Value(1400);
+  constexpr Value LazyThreshold1 =  Value(1565);
-  constexpr Value LazyThreshold2 =  Value(1300);
+  constexpr Value LazyThreshold2 =  Value(1102);
-  constexpr Value SpaceThreshold = Value(12222);
+  constexpr Value SpaceThreshold = Value(11551);
-  constexpr Value NNUEThreshold1 =   Value(550);
+  constexpr Value NNUEThreshold1 =   Value(682);
-  constexpr Value NNUEThreshold2 =   Value(150);
+  constexpr Value NNUEThreshold2 =   Value(176);
 
   // KingAttackWeights[PieceType] contains king attack weights by piece type
   constexpr int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 81, 52, 44, 10 };
@@ -212,9 +213,9 @@ namespace {
     { S(-47,-59), S(-20,-25), S( 14, -8), S( 29, 12), S( 39, 21), S( 53, 40), // Bishop
       S( 53, 56), S( 60, 58), S( 62, 65), S( 69, 72), S( 78, 78), S( 83, 87),
       S( 91, 88), S( 96, 98) },
-    { S(-61,-82), S(-20,-17), S(  2, 23) ,S(  3, 40), S(  4, 72), S( 11,100), // Rook
+    { S(-60,-82), S(-24,-15), S(  0, 17) ,S(  3, 43), S(  4, 72), S( 14,100), // Rook
-      S( 22,104), S( 31,120), S( 39,134), S(40 ,138), S( 41,158), S( 47,163),
+      S( 20,102), S( 30,122), S( 41,133), S(41 ,139), S( 41,153), S( 45,160),
-      S( 59,168), S( 60,169), S( 64,173) },
+      S( 57,165), S( 58,170), S( 67,175) },
     { S(-29,-49), S(-16,-29), S( -8, -8), S( -8, 17), S( 18, 39), S( 25, 54), // Queen
       S( 23, 59), S( 37, 73), S( 41, 76), S( 54, 95), S( 65, 95) ,S( 68,101),
       S( 69,124), S( 70,128), S( 70,132), S( 70,133) ,S( 71,136), S( 72,140),
@@ -222,21 +223,26 @@ namespace {
       S(112,178), S(114,185), S(114,187), S(119,221) }
   };
 
+  // BishopPawns[distance from edge] contains a file-dependent penalty for pawns on
+  // squares of the same color as our bishop.
+  constexpr Score BishopPawns[int(FILE_NB) / 2] = {
+    S(3, 8), S(3, 9), S(2, 8), S(3, 8)
+  };
+
   // KingProtector[knight/bishop] contains penalty for each distance unit to own king
   constexpr Score KingProtector[] = { S(8, 9), S(6, 9) };
 
   // Outpost[knight/bishop] contains bonuses for each knight or bishop occupying a
   // pawn protected square on rank 4 to 6 which is also safe from a pawn attack.
-  constexpr Score Outpost[] = { S(56, 34), S(31, 23) };
+  constexpr Score Outpost[] = { S(57, 38), S(31, 24) };
 
   // PassedRank[Rank] contains a bonus according to the rank of a passed pawn
   constexpr Score PassedRank[RANK_NB] = {
-    S(0, 0), S(9, 28), S(15, 31), S(17, 39), S(64, 70), S(171, 177), S(277, 260)
+    S(0, 0), S(7, 27), S(16, 32), S(17, 40), S(64, 71), S(170, 174), S(278, 262)
   };
 
-  // RookOnFile[semiopen/open] contains bonuses for each rook when there is
+  constexpr Score RookOnClosedFile = S(10, 5);
-  // no (friendly) pawn on the rook file.
+  constexpr Score RookOnOpenFile[] = { S(19, 6), S(47, 26) };
-  constexpr Score RookOnFile[] = { S(19, 7), S(48, 27) };
 
   // ThreatByMinor/ByRook[attacked PieceType] contains bonuses according to
   // which piece type attacks which one. Attacks on lesser pieces which are
@@ -250,9 +256,8 @@ namespace {
   };
 
   // Assorted bonuses and penalties
-  constexpr Score BadOutpost          = S( -7, 36);
+  constexpr Score UncontestedOutpost  = S(  1, 10);
   constexpr Score BishopOnKingRing    = S( 24,  0);
-  constexpr Score BishopPawns         = S(  3,  7);
   constexpr Score BishopXRayPawns     = S(  4,  5);
   constexpr Score CorneredBishop      = S( 50, 50);
   constexpr Score FlankAttacks        = S(  8,  0);
@@ -265,7 +270,6 @@ namespace {
   constexpr Score ReachableOutpost    = S( 31, 22);
   constexpr Score RestrictedPiece     = S(  7,  7);
   constexpr Score RookOnKingRing      = S( 16,  0);
-  constexpr Score RookOnQueenFile     = S(  6, 11);
   constexpr Score SliderOnQueen       = S( 60, 18);
   constexpr Score ThreatByKing        = S( 24, 89);
   constexpr Score ThreatByPawnPush    = S( 48, 39);
@@ -384,15 +388,15 @@ namespace {
     constexpr Direction Down = -pawn_push(Us);
     constexpr Bitboard OutpostRanks = (Us == WHITE ? Rank4BB | Rank5BB | Rank6BB
                                                    : Rank5BB | Rank4BB | Rank3BB);
-    const Square* pl = pos.squares<Pt>(Us);
+    Bitboard b1 = pos.pieces(Us, Pt);
-
     Bitboard b, bb;
     Score score = SCORE_ZERO;
 
     attackedBy[Us][Pt] = 0;
 
-    for (Square s = *pl; s != SQ_NONE; s = *++pl)
+    while (b1) {
-    {
+        Square s = pop_lsb(&b1);
+
         // Find attacked squares, including x-ray attacks for bishops and rooks
         b = Pt == BISHOP ? attacks_bb<BISHOP>(s, pos.pieces() ^ pos.pieces(QUEEN))
           : Pt ==   ROOK ? attacks_bb<  ROOK>(s, pos.pieces() ^ pos.pieces(QUEEN) ^ pos.pieces(Us, ROOK))
@@ -419,13 +423,12 @@ namespace {
             score += BishopOnKingRing;
 
         int mob = popcount(b & mobilityArea[Us]);
-
         mobility[Us] += MobilityBonus[Pt - 2][mob];
 
         if (Pt == BISHOP || Pt == KNIGHT)
         {
             // Bonus if the piece is on an outpost square or can reach one
-            // Reduced bonus for knights (BadOutpost) if few relevant targets
+            // Bonus for knights (UncontestedOutpost) if few relevant targets
             bb = OutpostRanks & (attackedBy[Us][PAWN] | shift<Down>(pos.pieces(PAWN)))
                               & ~pe->pawn_attacks_span(Them);
             Bitboard targets = pos.pieces(Them) & ~pos.pieces(PAWN);
@@ -434,7 +437,7 @@ namespace {
                 && bb & s & ~CenterFiles // on a side outpost
                 && !(b & targets)        // no relevant attacks
                 && (!more_than_one(targets & (s & QueenSide ? QueenSide : KingSide))))
-                score += BadOutpost;
+                score += UncontestedOutpost * popcount(pos.pieces(PAWN) & (s & QueenSide ? QueenSide : KingSide));
             else if (bb & s)
                 score += Outpost[Pt == BISHOP];
             else if (Pt == KNIGHT && bb & b & ~pos.pieces(Us))
@@ -447,14 +450,14 @@ namespace {
             // Penalty if the piece is far from the king
             score -= KingProtector[Pt == BISHOP] * distance(pos.square<KING>(Us), s);
 
-            if (Pt == BISHOP)
+            if constexpr (Pt == BISHOP)
             {
                 // Penalty according to the number of our pawns on the same color square as the
                 // bishop, bigger when the center files are blocked with pawns and smaller
                 // when the bishop is outside the pawn chain.
                 Bitboard blocked = pos.pieces(Us, PAWN) & shift<Down>(pos.pieces());
 
-                score -= BishopPawns * pos.pawns_on_same_color_squares(Us, s)
+                score -= BishopPawns[edge_distance(file_of(s))] * pos.pawns_on_same_color_squares(Us, s)
                                      * (!(attackedBy[Us][PAWN] & s) + popcount(blocked & CenterFiles));
 
                 // Penalty for all enemy pawns x-rayed
@@ -479,26 +482,34 @@ namespace {
             }
         }
 
-        if (Pt == ROOK)
+        if constexpr (Pt == ROOK)
         {
-            // Bonus for rook on the same file as a queen
+            // Bonuses for rook on a (semi-)open or closed file
-            if (file_bb(s) & pos.pieces(QUEEN))
-                score += RookOnQueenFile;
-
-            // Bonus for rook on an open or semi-open file
             if (pos.is_on_semiopen_file(Us, s))
-                score += RookOnFile[pos.is_on_semiopen_file(Them, s)];
-
-            // Penalty when trapped by the king, even more if the king cannot castle
-            else if (mob <= 3)
             {
-                File kf = file_of(pos.square<KING>(Us));
+                score += RookOnOpenFile[pos.is_on_semiopen_file(Them, s)];
-                if ((kf < FILE_E) == (file_of(s) < kf))
+            }
-                    score -= TrappedRook * (1 + !pos.castling_rights(Us));
+            else
+            {
+                // If our pawn on this file is blocked, increase penalty
+                if ( pos.pieces(Us, PAWN)
+                   & shift<Down>(pos.pieces())
+                   & file_bb(s))
+                {
+                    score -= RookOnClosedFile;
+                }
+
+                // Penalty when trapped by the king, even more if the king cannot castle
+                if (mob <= 3)
+                {
+                    File kf = file_of(pos.square<KING>(Us));
+                    if ((kf < FILE_E) == (file_of(s) < kf))
+                        score -= TrappedRook * (1 + !pos.castling_rights(Us));
+                }
             }
         }
 
-        if (Pt == QUEEN)
+        if constexpr (Pt == QUEEN)
         {
             // Penalty if any relative pin or discovered attack against the queen
             Bitboard queenPinners;
@@ -506,7 +517,7 @@ namespace {
                 score -= WeakQueen;
         }
     }
-    if (T)
+    if constexpr (T)
         Trace::add(Pt, Us, score);
 
     return score;
@@ -582,18 +593,18 @@ namespace {
     int kingFlankAttack  = popcount(b1) + popcount(b2);
     int kingFlankDefense = popcount(b3);
 
-    kingDanger +=        kingAttackersCount[Them] * kingAttackersWeight[Them]
+    kingDanger +=        kingAttackersCount[Them] * kingAttackersWeight[Them] // (~10 Elo)
-                 + 185 * popcount(kingRing[Us] & weak)
+                 + 183 * popcount(kingRing[Us] & weak)                        // (~15 Elo)
-                 + 148 * popcount(unsafeChecks)
+                 + 148 * popcount(unsafeChecks)                               // (~4 Elo)
-                 +  98 * popcount(pos.blockers_for_king(Us))
+                 +  98 * popcount(pos.blockers_for_king(Us))                  // (~2 Elo)
-                 +  69 * kingAttacksCount[Them]
+                 +  69 * kingAttacksCount[Them]                               // (~0.5 Elo)
-                 +   3 * kingFlankAttack * kingFlankAttack / 8
+                 +   3 * kingFlankAttack * kingFlankAttack / 8                // (~0.5 Elo)
-                 +       mg_value(mobility[Them] - mobility[Us])
+                 +       mg_value(mobility[Them] - mobility[Us])              // (~0.5 Elo)
-                 - 873 * !pos.count<QUEEN>(Them)
+                 - 873 * !pos.count<QUEEN>(Them)                              // (~24 Elo)
-                 - 100 * bool(attackedBy[Us][KNIGHT] & attackedBy[Us][KING])
+                 - 100 * bool(attackedBy[Us][KNIGHT] & attackedBy[Us][KING])  // (~5 Elo)
-                 -   6 * mg_value(score) / 8
+                 -   6 * mg_value(score) / 8                                  // (~8 Elo)
-                 -   4 * kingFlankDefense
+                 -   4 * kingFlankDefense                                     // (~5 Elo)
-                 +  37;
+                 +  37;                                                       // (~0.5 Elo)
 
     // Transform the kingDanger units into a Score, and subtract it from the evaluation
     if (kingDanger > 100)
@@ -606,7 +617,7 @@ namespace {
     // Penalty if king flank is under attack, potentially moving toward the king
     score -= FlankAttacks * kingFlankAttack;
 
-    if (T)
+    if constexpr (T)
         Trace::add(KING, Us, score);
 
     return score;
@@ -707,7 +718,7 @@ namespace {
         score += SliderOnQueen * popcount(b & safe & attackedBy2[Us]) * (1 + queenImbalance);
     }
 
-    if (T)
+    if constexpr (T)
         Trace::add(THREAT, Us, score);
 
     return score;
@@ -777,14 +788,16 @@ namespace {
                 bb = forward_file_bb(Them, s) & pos.pieces(ROOK, QUEEN);
 
                 if (!(pos.pieces(Them) & bb))
-                    unsafeSquares &= attackedBy[Them][ALL_PIECES];
+                    unsafeSquares &= attackedBy[Them][ALL_PIECES] | pos.pieces(Them);
 
-                // If there are no enemy attacks on passed pawn span, assign a big bonus.
+                // If there are no enemy pieces or attacks on passed pawn span, assign a big bonus.
+                // Or if there is some, but they are all attacked by our pawns, assign a bit smaller bonus.
                 // Otherwise assign a smaller bonus if the path to queen is not attacked
                 // and even smaller bonus if it is attacked but block square is not.
-                int k = !unsafeSquares                    ? 35 :
+                int k = !unsafeSquares                    ? 36 :
-                        !(unsafeSquares & squaresToQueen) ? 20 :
+                !(unsafeSquares & ~attackedBy[Us][PAWN])  ? 30 :
-                        !(unsafeSquares & blockSq)        ?  9 :
+                        !(unsafeSquares & squaresToQueen) ? 17 :
+                        !(unsafeSquares & blockSq)        ?  7 :
                                                              0 ;
 
                 // Assign a larger bonus if the block square is defended
@@ -798,7 +811,7 @@ namespace {
         score += bonus - PassedFile * edge_distance(file_of(s));
     }
 
-    if (T)
+    if constexpr (T)
         Trace::add(PASSED, Us, score);
 
     return score;
@@ -833,11 +846,13 @@ namespace {
     behind |= shift<Down>(behind);
     behind |= shift<Down+Down>(behind);
 
+    // Compute space score based on the number of safe squares and number of our pieces
+    // increased with number of total blocked pawns in position.
     int bonus = popcount(safe) + popcount(behind & safe & ~attackedBy[Them][ALL_PIECES]);
     int weight = pos.count<ALL_PIECES>(Us) - 3 + std::min(pe->blocked_count(), 9);
     Score score = make_score(bonus * weight * weight / 16, 0);
 
-    if (T)
+    if constexpr (T)
         Trace::add(SPACE, Us, score);
 
     return score;
@@ -852,7 +867,7 @@ namespace {
   Value Evaluation<T>::winnable(Score score) const {
 
     int outflanking =  distance<File>(pos.square<KING>(WHITE), pos.square<KING>(BLACK))
-                     - distance<Rank>(pos.square<KING>(WHITE), pos.square<KING>(BLACK));
+                    + int(rank_of(pos.square<KING>(WHITE)) - rank_of(pos.square<KING>(BLACK)));
 
     bool pawnsOnBothFlanks =   (pos.pieces(PAWN) & QueenSide)
                             && (pos.pieces(PAWN) & KingSide);
@@ -894,23 +909,37 @@ namespace {
     {
         if (pos.opposite_bishops())
         {
+            // For pure opposite colored bishops endgames use scale factor
+            // based on the number of passed pawns of the strong side.
             if (   pos.non_pawn_material(WHITE) == BishopValueMg
                 && pos.non_pawn_material(BLACK) == BishopValueMg)
                 sf = 18 + 4 * popcount(pe->passed_pawns(strongSide));
+            // For every other opposite colored bishops endgames use scale factor
+            // based on the number of all pieces of the strong side.
             else
                 sf = 22 + 3 * pos.count<ALL_PIECES>(strongSide);
         }
+        // For rook endgames with strong side not having overwhelming pawn number advantage
+        // and its pawns being on one flank and weak side protecting its pieces with a king
+        // use lower scale factor.
         else if (  pos.non_pawn_material(WHITE) == RookValueMg
                 && pos.non_pawn_material(BLACK) == RookValueMg
                 && pos.count<PAWN>(strongSide) - pos.count<PAWN>(~strongSide) <= 1
                 && bool(KingSide & pos.pieces(strongSide, PAWN)) != bool(QueenSide & pos.pieces(strongSide, PAWN))
                 && (attacks_bb<KING>(pos.square<KING>(~strongSide)) & pos.pieces(~strongSide, PAWN)))
             sf = 36;
+        // For queen vs no queen endgames use scale factor
+        // based on number of minors of side that doesn't have queen.
         else if (pos.count<QUEEN>() == 1)
             sf = 37 + 3 * (pos.count<QUEEN>(WHITE) == 1 ? pos.count<BISHOP>(BLACK) + pos.count<KNIGHT>(BLACK)
                                                         : pos.count<BISHOP>(WHITE) + pos.count<KNIGHT>(WHITE));
+        // In every other case use scale factor based on
+        // the number of pawns of the strong side reduced if pawns are on a single flank.
         else
-            sf = std::min(sf, 36 + 7 * pos.count<PAWN>(strongSide));
+            sf = std::min(sf, 36 + 7 * pos.count<PAWN>(strongSide)) - 4 * !pawnsOnBothFlanks;
+
+        // Reduce scale factor in case of pawns being on a single flank
+        sf -= 4 * !pawnsOnBothFlanks;
     }
 
     // Interpolate between the middlegame and (scaled by 'sf') endgame score
@@ -918,7 +947,7 @@ namespace {
        + eg * int(PHASE_MIDGAME - me->game_phase()) * ScaleFactor(sf) / SCALE_FACTOR_NORMAL;
     v /= PHASE_MIDGAME;
 
-    if (T)
+    if constexpr (T)
     {
         Trace::add(WINNABLE, make_score(u, eg * ScaleFactor(sf) / SCALE_FACTOR_NORMAL - eg_value(score)));
         Trace::add(TOTAL, make_score(mg, eg * ScaleFactor(sf) / SCALE_FACTOR_NORMAL));
@@ -990,7 +1019,7 @@ make_v:
     Value v = winnable(score);
 
     // In case of tracing add all remaining individual evaluation terms
-    if (T)
+    if constexpr (T)
     {
         Trace::add(MATERIAL, pos.psq_score());
         Trace::add(IMBALANCE, me->imbalance());
@@ -1023,8 +1052,8 @@ Value Eval::evaluate(const Position& pos) {
   {
       // Scale and shift NNUE for compatibility with search and classical evaluation
       auto  adjusted_NNUE = [&](){
-         int mat = pos.non_pawn_material() + PieceValue[MG][PAWN] * pos.count<PAWN>();
+         int mat = pos.non_pawn_material() + 2 * PawnValueMg * pos.count<PAWN>();
-         return NNUE::evaluate(pos) * (720 + mat / 32) / 1024 + Tempo;
+         return NNUE::evaluate(pos) * (641 + mat / 32 - 4 * pos.rule50_count()) / 1024 + Tempo;
       };
 
       // If there is PSQ imbalance use classical eval, with small probability if it is small
@@ -1033,16 +1062,20 @@ Value Eval::evaluate(const Position& pos) {
       bool  largePsq = psq * 16 > (NNUEThreshold1 + pos.non_pawn_material() / 64) * r50;
       bool  classical = largePsq || (psq > PawnValueMg / 4 && !(pos.this_thread()->nodes & 0xB));
 
-      v = classical ? Evaluation<NO_TRACE>(pos).value() : adjusted_NNUE();
+      // Use classical evaluation for really low piece endgames.
+      // The most critical case is a bishop + A/H file pawn vs naked king draw.
+      bool strongClassical = pos.non_pawn_material() < 2 * RookValueMg && pos.count<PAWN>() < 2;
+
+      v = classical || strongClassical ? Evaluation<NO_TRACE>(pos).value() : adjusted_NNUE();
 
       // If the classical eval is small and imbalance large, use NNUE nevertheless.
       // For the case of opposite colored bishops, switch to NNUE eval with
       // small probability if the classical eval is less than the threshold.
-      if (   largePsq
+      if (   largePsq && !strongClassical
-          && (abs(v) * 16 < NNUEThreshold2 * r50
+          && (   abs(v) * 16 < NNUEThreshold2 * r50
-          || (   pos.opposite_bishops()
+              || (   pos.opposite_bishops()
-              && abs(v) * 16 < (NNUEThreshold1 + pos.non_pawn_material() / 64) * r50
+                  && abs(v) * 16 < (NNUEThreshold1 + pos.non_pawn_material() / 64) * r50
-              && !(pos.this_thread()->nodes & 0xB))))
+                  && !(pos.this_thread()->nodes & 0xB))))
           v = adjusted_NNUE();
   }
 

DroidFishApp/src/main/cpp/stockfish/evaluate.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -36,7 +36,7 @@ namespace Eval {
   // The default net name MUST follow the format nn-[SHA256 first 12 digits].nnue
   // for the build process (profile-build and fishtest) to work. Do not change the
   // name of the macro, as it is used in the Makefile.
-  #define EvalFileDefaultName   "nn-baeb9ef2d183.nnue"
+  #define EvalFileDefaultName   "nn-62ef826d1a6d.nnue"
 
   namespace NNUE {
 

DroidFishApp/src/main/cpp/stockfish/main.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -21,15 +21,12 @@
 #include "bitboard.h"
 #include "endgame.h"
 #include "position.h"
+#include "psqt.h"
 #include "search.h"
+#include "syzygy/tbprobe.h"
 #include "thread.h"
 #include "tt.h"
 #include "uci.h"
-#include "syzygy/tbprobe.h"
-
-namespace PSQT {
-  void init();
-}
 
 int main(int argc, char* argv[]) {
 

DroidFishApp/src/main/cpp/stockfish/material.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -25,31 +25,36 @@
 using namespace std;
 
 namespace {
+  #define S(mg, eg) make_score(mg, eg)
 
   // Polynomial material imbalance parameters
 
-  constexpr int QuadraticOurs[][PIECE_TYPE_NB] = {
+  // One Score parameter for each pair (our piece, another of our pieces)
-    //            OUR PIECES
+  constexpr Score QuadraticOurs[][PIECE_TYPE_NB] = {
-    // pair pawn knight bishop rook queen
+    // OUR PIECE 2
-    {1438                               }, // Bishop pair
+    // bishop pair    pawn         knight       bishop       rook           queen
-    {  40,   38                         }, // Pawn
+    {S(1419, 1455)                                                                  }, // Bishop pair
-    {  32,  255, -62                    }, // Knight      OUR PIECES
+    {S( 101,   28), S( 37,  39)                                                     }, // Pawn
-    {   0,  104,   4,    0              }, // Bishop
+    {S(  57,   64), S(249, 187), S(-49, -62)                                        }, // Knight      OUR PIECE 1
-    { -26,   -2,  47,   105,  -208      }, // Rook
+    {S(   0,    0), S(118, 137), S( 10,  27), S(  0,   0)                           }, // Bishop
-    {-189,   24, 117,   133,  -134, -6  }  // Queen
+    {S( -63,  -68), S( -5,   3), S(100,  81), S(132, 118), S(-246, -244)            }, // Rook
+    {S(-210, -211), S( 37,  14), S(147, 141), S(161, 105), S(-158, -174), S(-9,-31) }  // Queen
   };
 
-  constexpr int QuadraticTheirs[][PIECE_TYPE_NB] = {
+  // One Score parameter for each pair (our piece, their piece)
-    //           THEIR PIECES
+  constexpr Score QuadraticTheirs[][PIECE_TYPE_NB] = {
-    // pair pawn knight bishop rook queen
+    // THEIR PIECE
-    {                                   }, // Bishop pair
+    // bishop pair   pawn         knight       bishop       rook         queen
-    {  36,                              }, // Pawn
+    {                                                                               }, // Bishop pair
-    {   9,   63,                        }, // Knight      OUR PIECES
+    {S(  33,  30)                                                                   }, // Pawn
-    {  59,   65,  42,                   }, // Bishop
+    {S(  46,  18), S(106,  84)                                                      }, // Knight      OUR PIECE
-    {  46,   39,  24,   -24,            }, // Rook
+    {S(  75,  35), S( 59,  44), S( 60,  15)                                         }, // Bishop
-    {  97,  100, -42,   137,  268,      }  // Queen
+    {S(  26,  35), S(  6,  22), S( 38,  39), S(-12,  -2)                            }, // Rook
+    {S(  97,  93), S(100, 163), S(-58, -91), S(112, 192), S(276, 225)               }  // Queen
   };
 
+  #undef S
+
   // Endgame evaluation and scaling functions are accessed directly and not through
   // the function maps because they correspond to more than one material hash key.
   Endgame<KXK>    EvaluateKXK[] = { Endgame<KXK>(WHITE),    Endgame<KXK>(BLACK) };
@@ -82,11 +87,11 @@ namespace {
   /// piece type for both colors.
 
   template<Color Us>
-  int imbalance(const int pieceCount[][PIECE_TYPE_NB]) {
+  Score imbalance(const int pieceCount[][PIECE_TYPE_NB]) {
 
     constexpr Color Them = ~Us;
 
-    int bonus = 0;
+    Score bonus = SCORE_ZERO;
 
     // Second-degree polynomial material imbalance, by Tord Romstad
     for (int pt1 = NO_PIECE_TYPE; pt1 <= QUEEN; ++pt1)
@@ -213,7 +218,7 @@ Entry* probe(const Position& pos) {
   { pos.count<BISHOP>(BLACK) > 1, pos.count<PAWN>(BLACK), pos.count<KNIGHT>(BLACK),
     pos.count<BISHOP>(BLACK)    , pos.count<ROOK>(BLACK), pos.count<QUEEN >(BLACK) } };
 
-  e->value = int16_t((imbalance<WHITE>(pieceCount) - imbalance<BLACK>(pieceCount)) / 16);
+  e->score = (imbalance<WHITE>(pieceCount) - imbalance<BLACK>(pieceCount)) / 16;
   return e;
 }
 

DroidFishApp/src/main/cpp/stockfish/material.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -37,8 +37,8 @@ namespace Material {
 
 struct Entry {
 
-  Score imbalance() const { return make_score(value, value); }
+  Score imbalance() const { return score; }
-  Phase game_phase() const { return gamePhase; }
+  Phase game_phase() const { return (Phase)gamePhase; }
   bool specialized_eval_exists() const { return evaluationFunction != nullptr; }
   Value evaluate(const Position& pos) const { return (*evaluationFunction)(pos); }
 
@@ -57,9 +57,9 @@ struct Entry {
   const EndgameBase<Value>* evaluationFunction;
   const EndgameBase<ScaleFactor>* scalingFunction[COLOR_NB]; // Could be one for each
                                                              // side (e.g. KPKP, KBPsK)
-  int16_t value;
+  Score score;
+  int16_t gamePhase;
   uint8_t factor[COLOR_NB];
-  Phase gamePhase;
 };
 
 typedef HashTable<Entry, 8192> Table;

DroidFishApp/src/main/cpp/stockfish/misc.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -65,7 +65,7 @@ namespace {
 
 /// Version number. If Version is left empty, then compile date in the format
 /// DD-MM-YY and show in engine_info.
-const string Version = "280920";
+const string Version = "13";
 
 /// Our fancy logging facility. The trick here is to replace cin.rdbuf() and
 /// cout.rdbuf() with two Tie objects that tie cin and cout to a file stream. We
@@ -583,11 +583,10 @@ namespace CommandLine {
 string argv0;            // path+name of the executable binary, as given by argv[0]
 string binaryDirectory;  // path of the executable directory
 string workingDirectory; // path of the working directory
-string pathSeparator;    // Separator for our current OS
 
 void init(int argc, char* argv[]) {
     (void)argc;
-    string separator;
+    string pathSeparator;
 
     // extract the path+name of the executable binary
     argv0 = argv[0];

DroidFishApp/src/main/cpp/stockfish/misc.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -24,6 +24,7 @@
 #include <ostream>
 #include <string>
 #include <vector>
+#include <cstdint>
 
 #include "types.h"
 
@@ -63,6 +64,17 @@ std::ostream& operator<<(std::ostream&, SyncCout);
 #define sync_cout std::cout << IO_LOCK
 #define sync_endl std::endl << IO_UNLOCK
 
+// `ptr` must point to an array of size at least
+// `sizeof(T) * N + alignment` bytes, where `N` is the
+// number of elements in the array.
+template <uintptr_t Alignment, typename T>
+T* align_ptr_up(T* ptr)
+{
+  static_assert(alignof(T) < Alignment);
+
+  const uintptr_t ptrint = reinterpret_cast<uintptr_t>(reinterpret_cast<char*>(ptr));
+  return reinterpret_cast<T*>(reinterpret_cast<char*>((ptrint + (Alignment - 1)) / Alignment * Alignment));
+}
 
 /// xorshift64star Pseudo-Random Number Generator
 /// This class is based on original code written and dedicated

DroidFishApp/src/main/cpp/stockfish/movegen.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -85,7 +85,7 @@ namespace {
 
             // Add pawn pushes which give discovered check. This is possible only
             // if the pawn is not on the same file as the enemy king, because we
-            // don't generate captures. Note that a possible discovery check
+            // don't generate captures. Note that a possible discovered check
             // promotion has been already generated amongst the captures.
             Bitboard dcCandidateQuiets = pos.blockers_for_king(Them) & pawnsNotOn7;
             if (dcCandidateQuiets)
@@ -134,7 +134,7 @@ namespace {
             moveList = make_promotions<Type, Up     >(moveList, pop_lsb(&b3), ksq);
     }
 
-    // Standard and en-passant captures
+    // Standard and en passant captures
     if (Type == CAPTURES || Type == EVASIONS || Type == NON_EVASIONS)
     {
         Bitboard b1 = shift<UpRight>(pawnsNotOn7) & enemies;
@@ -156,10 +156,8 @@ namespace {
         {
             assert(rank_of(pos.ep_square()) == relative_rank(Us, RANK_6));
 
-            // An en passant capture can be an evasion only if the checking piece
+            // An en passant capture cannot resolve a discovered check.
-            // is the double pushed pawn and so is in the target. Otherwise this
+            if (Type == EVASIONS && (target & (pos.ep_square() + Up)))
-            // is a discovery check and we are forced to do otherwise.
-            if (Type == EVASIONS && !(target & (pos.ep_square() - Up)))
                 return moveList;
 
             b1 = pawnsNotOn7 & pawn_attacks_bb(Them, pos.ep_square());
@@ -167,7 +165,7 @@ namespace {
             assert(b1);
 
             while (b1)
-                *moveList++ = make<ENPASSANT>(pop_lsb(&b1), pos.ep_square());
+                *moveList++ = make<EN_PASSANT>(pop_lsb(&b1), pos.ep_square());
         }
     }
 
@@ -175,29 +173,24 @@ namespace {
   }
 
 
-  template<Color Us, PieceType Pt, bool Checks>
+  template<PieceType Pt, bool Checks>
-  ExtMove* generate_moves(const Position& pos, ExtMove* moveList, Bitboard target) {
+  ExtMove* generate_moves(const Position& pos, ExtMove* moveList, Bitboard piecesToMove, Bitboard target) {
 
     static_assert(Pt != KING && Pt != PAWN, "Unsupported piece type in generate_moves()");
 
-    const Square* pl = pos.squares<Pt>(Us);
+    Bitboard bb = piecesToMove & pos.pieces(Pt);
 
-    for (Square from = *pl; from != SQ_NONE; from = *++pl)
+    if (!bb)
-    {
+        return moveList;
-        if (Checks)
-        {
-            if (    (Pt == BISHOP || Pt == ROOK || Pt == QUEEN)
-                && !(attacks_bb<Pt>(from) & target & pos.check_squares(Pt)))
-                continue;
 
-            if (pos.blockers_for_king(~Us) & from)
+    [[maybe_unused]] const Bitboard checkSquares = pos.check_squares(Pt);
-                continue;
+
-        }
+    while (bb) {
+        Square from = pop_lsb(&bb);
 
         Bitboard b = attacks_bb<Pt>(from, pos.pieces()) & target;
-
+        if constexpr (Checks)
-        if (Checks)
+            b &= checkSquares;
-            b &= pos.check_squares(Pt);
 
         while (b)
             *moveList++ = make_move(from, pop_lsb(&b));
@@ -209,8 +202,14 @@ namespace {
 
   template<Color Us, GenType Type>
   ExtMove* generate_all(const Position& pos, ExtMove* moveList) {
-    constexpr bool Checks = Type == QUIET_CHECKS; // Reduce template instantations
+
-    Bitboard target;
+    static_assert(Type != LEGAL, "Unsupported type in generate_all()");
+
+    constexpr bool Checks = Type == QUIET_CHECKS; // Reduce template instantiations
+    Bitboard target, piecesToMove = pos.pieces(Us);
+
+    if(Type == QUIET_CHECKS)
+        piecesToMove &= ~pos.blockers_for_king(~Us);
 
     switch (Type)
     {
@@ -230,15 +229,13 @@ namespace {
         case NON_EVASIONS:
             target = ~pos.pieces(Us);
             break;
-        default:
-            static_assert(true, "Unsupported type in generate_all()");
     }
 
     moveList = generate_pawn_moves<Us, Type>(pos, moveList, target);
-    moveList = generate_moves<Us, KNIGHT, Checks>(pos, moveList, target);
+    moveList = generate_moves<KNIGHT, Checks>(pos, moveList, piecesToMove, target);
-    moveList = generate_moves<Us, BISHOP, Checks>(pos, moveList, target);
+    moveList = generate_moves<BISHOP, Checks>(pos, moveList, piecesToMove, target);
-    moveList = generate_moves<Us,   ROOK, Checks>(pos, moveList, target);
+    moveList = generate_moves<  ROOK, Checks>(pos, moveList, piecesToMove, target);
-    moveList = generate_moves<Us,  QUEEN, Checks>(pos, moveList, target);
+    moveList = generate_moves< QUEEN, Checks>(pos, moveList, piecesToMove, target);
 
     if (Type != QUIET_CHECKS && Type != EVASIONS)
     {
@@ -260,7 +257,7 @@ namespace {
 
 
 /// <CAPTURES>     Generates all pseudo-legal captures plus queen and checking knight promotions
-/// <QUIETS>       Generates all pseudo-legal non-captures and underpromotions(except checking knight)
+/// <QUIETS>       Generates all pseudo-legal non-captures and underpromotions (except checking knight)
 /// <NON_EVASIONS> Generates all pseudo-legal captures and non-captures
 ///
 /// Returns a pointer to the end of the move list.
@@ -283,8 +280,8 @@ template ExtMove* generate<QUIETS>(const Position&, ExtMove*);
 template ExtMove* generate<NON_EVASIONS>(const Position&, ExtMove*);
 
 
-/// generate<QUIET_CHECKS> generates all pseudo-legal non-captures.
+/// generate<QUIET_CHECKS> generates all pseudo-legal non-captures giving check,
-/// Returns a pointer to the end of the move list.
+/// except castling. Returns a pointer to the end of the move list.
 template<>
 ExtMove* generate<QUIET_CHECKS>(const Position& pos, ExtMove* moveList) {
 
@@ -357,7 +354,7 @@ ExtMove* generate<LEGAL>(const Position& pos, ExtMove* moveList) {
   moveList = pos.checkers() ? generate<EVASIONS    >(pos, moveList)
                             : generate<NON_EVASIONS>(pos, moveList);
   while (cur != moveList)
-      if (   (pinned || from_sq(*cur) == ksq || type_of(*cur) == ENPASSANT)
+      if (  ((pinned && pinned & from_sq(*cur)) || from_sq(*cur) == ksq || type_of(*cur) == EN_PASSANT)
           && !pos.legal(*cur))
           *cur = (--moveList)->move;
       else

DroidFishApp/src/main/cpp/stockfish/movegen.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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

DroidFishApp/src/main/cpp/stockfish/movepick.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -73,8 +73,9 @@ MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const ButterflyHist
   assert(d <= 0);
 
   stage = (pos.checkers() ? EVASION_TT : QSEARCH_TT) +
-           !(ttm && (depth > DEPTH_QS_RECAPTURES || to_sq(ttm) == recaptureSquare)
+          !(   ttm
-                 && pos.pseudo_legal(ttm));
+            && (pos.checkers() || depth > DEPTH_QS_RECAPTURES || to_sq(ttm) == recaptureSquare)
+            && pos.pseudo_legal(ttm));
 }
 
 /// MovePicker constructor for ProbCut: we generate captures with SEE greater
@@ -98,15 +99,15 @@ void MovePicker::score() {
   static_assert(Type == CAPTURES || Type == QUIETS || Type == EVASIONS, "Wrong type");
 
   for (auto& m : *this)
-      if (Type == CAPTURES)
+      if constexpr (Type == CAPTURES)
           m.value =  int(PieceValue[MG][pos.piece_on(to_sq(m))]) * 6
                    + (*captureHistory)[pos.moved_piece(m)][to_sq(m)][type_of(pos.piece_on(to_sq(m)))];
 
-      else if (Type == QUIETS)
+      else if constexpr (Type == QUIETS)
           m.value =      (*mainHistory)[pos.side_to_move()][from_to(m)]
                    + 2 * (*continuationHistory[0])[pos.moved_piece(m)][to_sq(m)]
-                   + 2 * (*continuationHistory[1])[pos.moved_piece(m)][to_sq(m)]
+                   +     (*continuationHistory[1])[pos.moved_piece(m)][to_sq(m)]
-                   + 2 * (*continuationHistory[3])[pos.moved_piece(m)][to_sq(m)]
+                   +     (*continuationHistory[3])[pos.moved_piece(m)][to_sq(m)]
                    +     (*continuationHistory[5])[pos.moved_piece(m)][to_sq(m)]
                    + (ply < MAX_LPH ? std::min(4, depth / 3) * (*lowPlyHistory)[ply][from_to(m)] : 0);
 
@@ -116,8 +117,8 @@ void MovePicker::score() {
               m.value =  PieceValue[MG][pos.piece_on(to_sq(m))]
                        - Value(type_of(pos.moved_piece(m)));
           else
-              m.value =  (*mainHistory)[pos.side_to_move()][from_to(m)]
+              m.value =      (*mainHistory)[pos.side_to_move()][from_to(m)]
-                       + (*continuationHistory[0])[pos.moved_piece(m)][to_sq(m)]
+                       + 2 * (*continuationHistory[0])[pos.moved_piece(m)][to_sq(m)]
                        - (1 << 28);
       }
 }
@@ -141,7 +142,7 @@ Move MovePicker::select(Pred filter) {
 }
 
 /// MovePicker::next_move() is the most important method of the MovePicker class. It
-/// returns a new pseudo legal move every time it is called until there are no more
+/// returns a new pseudo-legal move every time it is called until there are no more
 /// moves left, picking the move with the highest score from a list of generated moves.
 Move MovePicker::next_move(bool skipQuiets) {
 

DroidFishApp/src/main/cpp/stockfish/movepick.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -84,7 +84,7 @@ enum StatsType { NoCaptures, Captures };
 /// unsuccessful during the current search, and is used for reduction and move
 /// ordering decisions. It uses 2 tables (one for each color) indexed by
 /// the move's from and to squares, see www.chessprogramming.org/Butterfly_Boards
-typedef Stats<int16_t, 10692, COLOR_NB, int(SQUARE_NB) * int(SQUARE_NB)> ButterflyHistory;
+typedef Stats<int16_t, 13365, COLOR_NB, int(SQUARE_NB) * int(SQUARE_NB)> ButterflyHistory;
 
 /// At higher depths LowPlyHistory records successful quiet moves near the root
 /// and quiet moves which are/were in the PV (ttPv). It is cleared with each new
@@ -108,12 +108,12 @@ typedef Stats<int16_t, 29952, PIECE_NB, SQUARE_NB> PieceToHistory;
 typedef Stats<PieceToHistory, NOT_USED, PIECE_NB, SQUARE_NB> ContinuationHistory;
 
 
-/// MovePicker class is used to pick one pseudo legal move at a time from the
+/// MovePicker class is used to pick one pseudo-legal move at a time from the
 /// current position. The most important method is next_move(), which returns a
-/// new pseudo legal move each time it is called, until there are no moves left,
+/// new pseudo-legal move each time it is called, until there are no moves left,
-/// when MOVE_NONE is returned. In order to improve the efficiency of the alpha
+/// when MOVE_NONE is returned. In order to improve the efficiency of the
-/// beta algorithm, MovePicker attempts to return the moves which are most likely
+/// alpha-beta algorithm, MovePicker attempts to return the moves which are most
-/// to get a cut-off first.
+/// likely to get a cut-off first.
 class MovePicker {
 
   enum PickType { Next, Best };

DroidFishApp/src/main/cpp/stockfish/nnue/architectures/halfkp_256x2-32-32.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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

DroidFishApp/src/main/cpp/stockfish/nnue/evaluate_nnue.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -25,32 +25,12 @@
 #include "../position.h"
 #include "../misc.h"
 #include "../uci.h"
+#include "../types.h"
 
 #include "evaluate_nnue.h"
 
 namespace Eval::NNUE {
 
-  const uint32_t kpp_board_index[PIECE_NB][COLOR_NB] = {
-   // convention: W - us, B - them
-   // viewed from other side, W and B are reversed
-      { PS_NONE,     PS_NONE     },
-      { PS_W_PAWN,   PS_B_PAWN   },
-      { PS_W_KNIGHT, PS_B_KNIGHT },
-      { PS_W_BISHOP, PS_B_BISHOP },
-      { PS_W_ROOK,   PS_B_ROOK   },
-      { PS_W_QUEEN,  PS_B_QUEEN  },
-      { PS_W_KING,   PS_B_KING   },
-      { PS_NONE,     PS_NONE     },
-      { PS_NONE,     PS_NONE     },
-      { PS_B_PAWN,   PS_W_PAWN   },
-      { PS_B_KNIGHT, PS_W_KNIGHT },
-      { PS_B_BISHOP, PS_W_BISHOP },
-      { PS_B_ROOK,   PS_W_ROOK   },
-      { PS_B_QUEEN,  PS_W_QUEEN  },
-      { PS_B_KING,   PS_W_KING   },
-      { PS_NONE,     PS_NONE     }
-  };
-
   // Input feature converter
   LargePagePtr<FeatureTransformer> feature_transformer;
 
@@ -126,10 +106,28 @@ namespace Eval::NNUE {
   // Evaluation function. Perform differential calculation.
   Value evaluate(const Position& pos) {
 
-    alignas(kCacheLineSize) TransformedFeatureType
+    // We manually align the arrays on the stack because with gcc < 9.3
-        transformed_features[FeatureTransformer::kBufferSize];
+    // overaligning stack variables with alignas() doesn't work correctly.
+
+    constexpr uint64_t alignment = kCacheLineSize;
+
+#if defined(ALIGNAS_ON_STACK_VARIABLES_BROKEN)
+    TransformedFeatureType transformed_features_unaligned[
+      FeatureTransformer::kBufferSize + alignment / sizeof(TransformedFeatureType)];
+    char buffer_unaligned[Network::kBufferSize + alignment];
+
+    auto* transformed_features = align_ptr_up<alignment>(&transformed_features_unaligned[0]);
+    auto* buffer = align_ptr_up<alignment>(&buffer_unaligned[0]);
+#else
+    alignas(alignment)
+      TransformedFeatureType transformed_features[FeatureTransformer::kBufferSize];
+    alignas(alignment) char buffer[Network::kBufferSize];
+#endif
+
+    ASSERT_ALIGNED(transformed_features, alignment);
+    ASSERT_ALIGNED(buffer, alignment);
+
     feature_transformer->Transform(pos, transformed_features);
-    alignas(kCacheLineSize) char buffer[Network::kBufferSize];
     const auto output = network->Propagate(transformed_features, buffer);
 
     return static_cast<Value>(output[0] / FV_SCALE);

DroidFishApp/src/main/cpp/stockfish/nnue/evaluate_nnue.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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

DroidFishApp/src/main/cpp/stockfish/nnue/features/feature_set.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -43,90 +43,6 @@ namespace Eval::NNUE::Features {
   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]) {
-
-      auto collect_for_one = [&](const DirtyPiece& dp) {
-        for (Color perspective : { WHITE, BLACK }) {
-          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, dp, trigger, perspective,
-                &removed[perspective], &added[perspective]);
-          }
-        }
-      };
-
-      auto collect_for_two = [&](const DirtyPiece& dp1, const DirtyPiece& dp2) {
-        for (Color perspective : { WHITE, BLACK }) {
-          switch (trigger) {
-            case TriggerEvent::kFriendKingMoved:
-              reset[perspective] = dp1.piece[0] == make_piece(perspective, KING)
-                                || dp2.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, dp1, trigger, perspective,
-                &removed[perspective], &added[perspective]);
-            Derived::CollectChangedIndices(
-                pos, dp2, trigger, perspective,
-                &removed[perspective], &added[perspective]);
-          }
-        }
-      };
-
-      if (pos.state()->previous->accumulator.computed_accumulation) {
-        const auto& prev_dp = pos.state()->dirtyPiece;
-        if (prev_dp.dirty_num == 0) return;
-        collect_for_one(prev_dp);
-      } else {
-        const auto& prev_dp = pos.state()->previous->dirtyPiece;
-        if (prev_dp.dirty_num == 0) {
-          const auto& prev2_dp = pos.state()->dirtyPiece;
-          if (prev2_dp.dirty_num == 0) return;
-          collect_for_one(prev2_dp);
-        } else {
-          const auto& prev2_dp = pos.state()->dirtyPiece;
-          if (prev2_dp.dirty_num == 0) {
-            collect_for_one(prev_dp);
-          } else {
-            collect_for_two(prev_dp, prev2_dp);
-          }
-        }
-      }
-    }
   };
 
   // Class template that represents the feature set
@@ -146,30 +62,6 @@ namespace Eval::NNUE::Features {
         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 DirtyPiece& dp, const TriggerEvent trigger, const Color perspective,
-        IndexList* const removed, IndexList* const added) {
-
-      if (FeatureType::kRefreshTrigger == trigger) {
-        FeatureType::AppendChangedIndices(pos, dp, 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

DroidFishApp/src/main/cpp/stockfish/nnue/features/features_common.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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

DroidFishApp/src/main/cpp/stockfish/nnue/features/half_kp.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -28,12 +28,9 @@ namespace Eval::NNUE::Features {
     return Square(int(s) ^ (bool(perspective) * 63));
   }
 
-  // Find the index of the feature quantity from the king position and PieceSquare
+  // Index of a feature for a given king position and another piece on some square
-  template <Side AssociatedKing>
+  inline IndexType make_index(Color perspective, Square s, Piece pc, Square ksq) {
-  inline IndexType HalfKP<AssociatedKing>::MakeIndex(
+    return IndexType(orient(perspective, s) + kpp_board_index[perspective][pc] + PS_END * ksq);
-      Color perspective, Square s, Piece pc, Square ksq) {
-
-    return IndexType(orient(perspective, s) + kpp_board_index[pc][perspective] + PS_END * ksq);
   }
 
   // Get a list of indices for active features
@@ -45,7 +42,7 @@ namespace Eval::NNUE::Features {
     Bitboard bb = pos.pieces() & ~pos.pieces(KING);
     while (bb) {
       Square s = pop_lsb(&bb);
-      active->push_back(MakeIndex(perspective, s, pos.piece_on(s), ksq));
+      active->push_back(make_index(perspective, s, pos.piece_on(s), ksq));
     }
   }
 
@@ -60,9 +57,9 @@ namespace Eval::NNUE::Features {
       Piece pc = dp.piece[i];
       if (type_of(pc) == KING) continue;
       if (dp.from[i] != SQ_NONE)
-        removed->push_back(MakeIndex(perspective, dp.from[i], pc, ksq));
+        removed->push_back(make_index(perspective, dp.from[i], pc, ksq));
       if (dp.to[i] != SQ_NONE)
-        added->push_back(MakeIndex(perspective, dp.to[i], pc, ksq));
+        added->push_back(make_index(perspective, dp.to[i], pc, ksq));
     }
   }
 

DroidFishApp/src/main/cpp/stockfish/nnue/features/half_kp.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -52,10 +52,6 @@ namespace Eval::NNUE::Features {
     // Get a list of indices for recently changed features
     static void AppendChangedIndices(const Position& pos, const DirtyPiece& dp, Color perspective,
                                      IndexList* removed, IndexList* added);
-
-   private:
-    // Index of a feature for a given king position and another piece on some square
-    static IndexType MakeIndex(Color perspective, Square s, Piece pc, Square sq_k);
   };
 
 }  // namespace Eval::NNUE::Features

DroidFishApp/src/main/cpp/stockfish/nnue/features/index_list.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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

DroidFishApp/src/main/cpp/stockfish/nnue/layers/affine_transform.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -41,6 +41,11 @@ namespace Eval::NNUE::Layers {
     static constexpr IndexType kOutputDimensions = OutputDimensions;
     static constexpr IndexType kPaddedInputDimensions =
         CeilToMultiple<IndexType>(kInputDimensions, kMaxSimdWidth);
+#if defined (USE_AVX512)
+    static constexpr const IndexType kOutputSimdWidth = kSimdWidth / 2;
+#elif defined (USE_SSSE3)
+    static constexpr const IndexType kOutputSimdWidth = kSimdWidth / 4;
+#endif
 
     // Size of forward propagation buffer used in this layer
     static constexpr std::size_t kSelfBufferSize =
@@ -65,7 +70,58 @@ namespace Eval::NNUE::Layers {
       for (std::size_t i = 0; i < kOutputDimensions; ++i)
         biases_[i] = read_little_endian<BiasType>(stream);
       for (std::size_t i = 0; i < kOutputDimensions * kPaddedInputDimensions; ++i)
+#if !defined (USE_SSSE3)
         weights_[i] = read_little_endian<WeightType>(stream);
+#else
+        weights_[
+          (i / 4) % (kPaddedInputDimensions / 4) * kOutputDimensions * 4 +
+          i / kPaddedInputDimensions * 4 +
+          i % 4
+        ] = read_little_endian<WeightType>(stream);
+
+      // Determine if eights of weight and input products can be summed using 16bits
+      // without saturation. We assume worst case combinations of 0 and 127 for all inputs.
+      if (kOutputDimensions > 1 && !stream.fail())
+      {
+          canSaturate16.count = 0;
+#if !defined(USE_VNNI)
+          for (IndexType i = 0; i < kPaddedInputDimensions; i += 16)
+              for (IndexType j = 0; j < kOutputDimensions; ++j)
+                  for (int x = 0; x < 2; ++x)
+                  {
+                      WeightType* w = &weights_[i * kOutputDimensions + j * 4 + x * 2];
+                      int sum[2] = {0, 0};
+                      for (int k = 0; k < 8; ++k)
+                      {
+                          IndexType idx = k / 2 * kOutputDimensions * 4 + k % 2;
+                          sum[w[idx] < 0] += w[idx];
+                      }
+                      for (int sign : {-1, 1})
+                          while (sign * sum[sign == -1] > 258)
+                          {
+                              int maxK = 0, maxW = 0;
+                              for (int k = 0; k < 8; ++k)
+                              {
+                                  IndexType idx = k / 2 * kOutputDimensions * 4 + k % 2;
+                                  if (maxW < sign * w[idx])
+                                      maxK = k, maxW = sign * w[idx];
+                              }
+
+                              IndexType idx = maxK / 2 * kOutputDimensions * 4 + maxK % 2;
+                              sum[sign == -1] -= w[idx];
+                              canSaturate16.add(j, i + maxK / 2 * 4 + maxK % 2 + x * 2, w[idx]);
+                              w[idx] = 0;
+                          }
+                  }
+
+          // Non functional optimization for faster more linear access
+          std::sort(canSaturate16.ids, canSaturate16.ids + canSaturate16.count,
+                    [](const typename CanSaturate::Entry& e1, const typename CanSaturate::Entry& e2)
+                    { return e1.in == e2.in ? e1.out < e2.out : e1.in < e2.in; });
+#endif
+      }
+#endif
+
       return !stream.fail();
     }
 
@@ -74,122 +130,246 @@ namespace Eval::NNUE::Layers {
         const TransformedFeatureType* transformed_features, char* buffer) const {
       const auto input = previous_layer_.Propagate(
           transformed_features, buffer + kSelfBufferSize);
+
+#if defined (USE_AVX512)
+
+      [[maybe_unused]] const __m512i kOnes512 = _mm512_set1_epi16(1);
+
+      [[maybe_unused]] auto m512_hadd = [](__m512i sum, int bias) -> int {
+        return _mm512_reduce_add_epi32(sum) + bias;
+      };
+
+      [[maybe_unused]] auto m512_add_dpbusd_epi32 = [=](__m512i& acc, __m512i a, __m512i b) {
+#if defined (USE_VNNI)
+        acc = _mm512_dpbusd_epi32(acc, a, b);
+#else
+        __m512i product0 = _mm512_maddubs_epi16(a, b);
+        product0 = _mm512_madd_epi16(product0, kOnes512);
+        acc = _mm512_add_epi32(acc, product0);
+#endif
+      };
+
+      [[maybe_unused]] auto m512_add_dpbusd_epi32x4 = [=](__m512i& acc, __m512i a0, __m512i b0, __m512i a1, __m512i b1,
+                                                                        __m512i a2, __m512i b2, __m512i a3, __m512i b3) {
+#if defined (USE_VNNI)
+        acc = _mm512_dpbusd_epi32(acc, a0, b0);
+        acc = _mm512_dpbusd_epi32(acc, a1, b1);
+        acc = _mm512_dpbusd_epi32(acc, a2, b2);
+        acc = _mm512_dpbusd_epi32(acc, a3, b3);
+#else
+        __m512i product0 = _mm512_maddubs_epi16(a0, b0);
+        __m512i product1 = _mm512_maddubs_epi16(a1, b1);
+        __m512i product2 = _mm512_maddubs_epi16(a2, b2);
+        __m512i product3 = _mm512_maddubs_epi16(a3, b3);
+        product0 = _mm512_add_epi16(product0, product1);
+        product2 = _mm512_add_epi16(product2, product3);
+        product0 = _mm512_add_epi16(product0, product2);
+        product0 = _mm512_madd_epi16(product0, kOnes512);
+        acc = _mm512_add_epi32(acc, product0);
+#endif
+      };
+
+#endif
+#if defined (USE_AVX2)
+
+      [[maybe_unused]] const __m256i kOnes256 = _mm256_set1_epi16(1);
+
+      [[maybe_unused]] auto m256_hadd = [](__m256i sum, int bias) -> int {
+        __m128i sum128 = _mm_add_epi32(_mm256_castsi256_si128(sum), _mm256_extracti128_si256(sum, 1));
+        sum128 = _mm_add_epi32(sum128, _mm_shuffle_epi32(sum128, _MM_PERM_BADC));
+        sum128 = _mm_add_epi32(sum128, _mm_shuffle_epi32(sum128, _MM_PERM_CDAB));
+        return _mm_cvtsi128_si32(sum128) + bias;
+      };
+
+      [[maybe_unused]] auto m256_add_dpbusd_epi32 = [=](__m256i& acc, __m256i a, __m256i b) {
+#if defined (USE_VNNI)
+        acc = _mm256_dpbusd_epi32(acc, a, b);
+#else
+        __m256i product0 = _mm256_maddubs_epi16(a, b);
+        product0 = _mm256_madd_epi16(product0, kOnes256);
+        acc = _mm256_add_epi32(acc, product0);
+#endif
+      };
+
+      [[maybe_unused]] auto m256_add_dpbusd_epi32x4 = [=](__m256i& acc, __m256i a0, __m256i b0, __m256i a1, __m256i b1,
+                                                                        __m256i a2, __m256i b2, __m256i a3, __m256i b3) {
+#if defined (USE_VNNI)
+        acc = _mm256_dpbusd_epi32(acc, a0, b0);
+        acc = _mm256_dpbusd_epi32(acc, a1, b1);
+        acc = _mm256_dpbusd_epi32(acc, a2, b2);
+        acc = _mm256_dpbusd_epi32(acc, a3, b3);
+#else
+        __m256i product0 = _mm256_maddubs_epi16(a0, b0);
+        __m256i product1 = _mm256_maddubs_epi16(a1, b1);
+        __m256i product2 = _mm256_maddubs_epi16(a2, b2);
+        __m256i product3 = _mm256_maddubs_epi16(a3, b3);
+        product0 = _mm256_add_epi16(product0, product1);
+        product2 = _mm256_add_epi16(product2, product3);
+        product0 = _mm256_add_epi16(product0, product2);
+        product0 = _mm256_madd_epi16(product0, kOnes256);
+        acc = _mm256_add_epi32(acc, product0);
+#endif
+      };
+
+#endif
+#if defined (USE_SSSE3)
+
+      [[maybe_unused]] const __m128i kOnes128 = _mm_set1_epi16(1);
+
+      [[maybe_unused]] auto m128_hadd = [](__m128i sum, int bias) -> int {
+        sum = _mm_add_epi32(sum, _mm_shuffle_epi32(sum, 0x4E)); //_MM_PERM_BADC
+        sum = _mm_add_epi32(sum, _mm_shuffle_epi32(sum, 0xB1)); //_MM_PERM_CDAB
+        return _mm_cvtsi128_si32(sum) + bias;
+      };
+
+      [[maybe_unused]] auto m128_add_dpbusd_epi32 = [=](__m128i& acc, __m128i a, __m128i b) {
+        __m128i product0 = _mm_maddubs_epi16(a, b);
+        product0 = _mm_madd_epi16(product0, kOnes128);
+        acc = _mm_add_epi32(acc, product0);
+      };
+
+      [[maybe_unused]] auto m128_add_dpbusd_epi32x4 = [=](__m128i& acc, __m128i a0, __m128i b0, __m128i a1, __m128i b1,
+                                                                        __m128i a2, __m128i b2, __m128i a3, __m128i b3) {
+        __m128i product0 = _mm_maddubs_epi16(a0, b0);
+        __m128i product1 = _mm_maddubs_epi16(a1, b1);
+        __m128i product2 = _mm_maddubs_epi16(a2, b2);
+        __m128i product3 = _mm_maddubs_epi16(a3, b3);
+        product0 = _mm_adds_epi16(product0, product1);
+        product2 = _mm_adds_epi16(product2, product3);
+        product0 = _mm_adds_epi16(product0, product2);
+        product0 = _mm_madd_epi16(product0, kOnes128);
+        acc = _mm_add_epi32(acc, product0);
+      };
+
+#endif
+
+#if defined (USE_AVX512)
+      using vec_t = __m512i;
+      #define vec_setzero _mm512_setzero_si512
+      #define vec_set_32 _mm512_set1_epi32
+      auto& vec_add_dpbusd_32 = m512_add_dpbusd_epi32;
+      auto& vec_add_dpbusd_32x4 = m512_add_dpbusd_epi32x4;
+      auto& vec_hadd = m512_hadd;
+#elif defined (USE_AVX2)
+      using vec_t = __m256i;
+      #define vec_setzero _mm256_setzero_si256
+      #define vec_set_32 _mm256_set1_epi32
+      auto& vec_add_dpbusd_32 = m256_add_dpbusd_epi32;
+      auto& vec_add_dpbusd_32x4 = m256_add_dpbusd_epi32x4;
+      auto& vec_hadd = m256_hadd;
+#elif defined (USE_SSSE3)
+      using vec_t = __m128i;
+      #define vec_setzero _mm_setzero_si128
+      #define vec_set_32 _mm_set1_epi32
+      auto& vec_add_dpbusd_32 = m128_add_dpbusd_epi32;
+      auto& vec_add_dpbusd_32x4 = m128_add_dpbusd_epi32x4;
+      auto& vec_hadd = m128_hadd;
+#endif
+
+#if defined (USE_SSSE3)
+
       const auto output = reinterpret_cast<OutputType*>(buffer);
+      const auto input_vector = reinterpret_cast<const vec_t*>(input);
 
-  #if defined(USE_AVX512)
+      static_assert(kOutputDimensions % kOutputSimdWidth == 0 || kOutputDimensions == 1);
-      constexpr IndexType kNumChunks = kPaddedInputDimensions / (kSimdWidth * 2);
-      const auto input_vector = reinterpret_cast<const __m512i*>(input);
-  #if !defined(USE_VNNI)
-      const __m512i kOnes = _mm512_set1_epi16(1);
-  #endif
 
-  #elif defined(USE_AVX2)
+      // kOutputDimensions is either 1 or a multiple of kSimdWidth
+      // because then it is also an input dimension.
+      if constexpr (kOutputDimensions % kOutputSimdWidth == 0)
+      {
+          constexpr IndexType kNumChunks = kPaddedInputDimensions / 4;
+
+          const auto input32 = reinterpret_cast<const std::int32_t*>(input);
+          vec_t* outptr = reinterpret_cast<vec_t*>(output);
+          std::memcpy(output, biases_, kOutputDimensions * sizeof(OutputType));
+
+          for (int i = 0; i < (int)kNumChunks - 3; i += 4)
+          {
+              const vec_t in0 = vec_set_32(input32[i + 0]);
+              const vec_t in1 = vec_set_32(input32[i + 1]);
+              const vec_t in2 = vec_set_32(input32[i + 2]);
+              const vec_t in3 = vec_set_32(input32[i + 3]);
+              const auto col0 = reinterpret_cast<const vec_t*>(&weights_[(i + 0) * kOutputDimensions * 4]);
+              const auto col1 = reinterpret_cast<const vec_t*>(&weights_[(i + 1) * kOutputDimensions * 4]);
+              const auto col2 = reinterpret_cast<const vec_t*>(&weights_[(i + 2) * kOutputDimensions * 4]);
+              const auto col3 = reinterpret_cast<const vec_t*>(&weights_[(i + 3) * kOutputDimensions * 4]);
+              for (int j = 0; j * kOutputSimdWidth < kOutputDimensions; ++j)
+                  vec_add_dpbusd_32x4(outptr[j], in0, col0[j], in1, col1[j], in2, col2[j], in3, col3[j]);
+          }
+          for (int i = 0; i < canSaturate16.count; ++i)
+              output[canSaturate16.ids[i].out] += input[canSaturate16.ids[i].in] * canSaturate16.ids[i].w;
+      }
+      else if constexpr (kOutputDimensions == 1)
+      {
+#if defined (USE_AVX512)
+          if constexpr (kPaddedInputDimensions % (kSimdWidth * 2) != 0)
+          {
+              constexpr IndexType kNumChunks = kPaddedInputDimensions / kSimdWidth;
+              const auto input_vector256 = reinterpret_cast<const __m256i*>(input);
+
+              __m256i sum0 = _mm256_setzero_si256();
+              const auto row0 = reinterpret_cast<const __m256i*>(&weights_[0]);
+
+              for (int j = 0; j < (int)kNumChunks; ++j)
+              {
+                  const __m256i in = input_vector256[j];
+                  m256_add_dpbusd_epi32(sum0, in, row0[j]);
+              }
+              output[0] = m256_hadd(sum0, biases_[0]);
+          }
+          else
+#endif
+          {
+#if defined (USE_AVX512)
+              constexpr IndexType kNumChunks = kPaddedInputDimensions / (kSimdWidth * 2);
+#else
+              constexpr IndexType kNumChunks = kPaddedInputDimensions / kSimdWidth;
+#endif
+              vec_t sum0 = vec_setzero();
+              const auto row0 = reinterpret_cast<const vec_t*>(&weights_[0]);
+
+              for (int j = 0; j < (int)kNumChunks; ++j)
+              {
+                  const vec_t in = input_vector[j];
+                  vec_add_dpbusd_32(sum0, in, row0[j]);
+              }
+              output[0] = vec_hadd(sum0, biases_[0]);
+          }
+      }
+
+#else
+
+// Use old implementation for the other architectures.
+
+      auto output = reinterpret_cast<OutputType*>(buffer);
+
+#if defined(USE_SSE2)
       constexpr IndexType kNumChunks = kPaddedInputDimensions / kSimdWidth;
-      const auto input_vector = reinterpret_cast<const __m256i*>(input);
-  #if !defined(USE_VNNI)
-      const __m256i kOnes = _mm256_set1_epi16(1);
-  #endif
-
-  #elif defined(USE_SSE2)
-      constexpr IndexType kNumChunks = kPaddedInputDimensions / kSimdWidth;
-  #ifndef USE_SSSE3
       const __m128i kZeros = _mm_setzero_si128();
-  #else
-      const __m128i kOnes = _mm_set1_epi16(1);
-  #endif
       const auto input_vector = reinterpret_cast<const __m128i*>(input);
 
-  #elif defined(USE_MMX)
+#elif defined(USE_MMX)
       constexpr IndexType kNumChunks = kPaddedInputDimensions / kSimdWidth;
       const __m64 kZeros = _mm_setzero_si64();
       const auto input_vector = reinterpret_cast<const __m64*>(input);
 
-  #elif defined(USE_NEON)
+#elif defined(USE_NEON)
       constexpr IndexType kNumChunks = kPaddedInputDimensions / kSimdWidth;
       const auto input_vector = reinterpret_cast<const int8x8_t*>(input);
-  #endif
+#endif
 
       for (IndexType i = 0; i < kOutputDimensions; ++i) {
         const IndexType offset = i * kPaddedInputDimensions;
 
-  #if defined(USE_AVX512)
+#if defined(USE_SSE2)
-        __m512i sum = _mm512_setzero_si512();
-        const auto row = reinterpret_cast<const __m512i*>(&weights_[offset]);
-        for (IndexType j = 0; j < kNumChunks; ++j) {
-  #if defined(USE_VNNI)
-            sum = _mm512_dpbusd_epi32(sum, _mm512_loadA_si512(&input_vector[j]), _mm512_load_si512(&row[j]));
-  #else
-            __m512i product = _mm512_maddubs_epi16(_mm512_loadA_si512(&input_vector[j]), _mm512_load_si512(&row[j]));
-            product = _mm512_madd_epi16(product, kOnes);
-            sum = _mm512_add_epi32(sum, product);
-  #endif
-        }
-
-        // Note: Changing kMaxSimdWidth from 32 to 64 breaks loading existing networks.
-        // As a result kPaddedInputDimensions may not be an even multiple of 64(512bit)
-        // and we have to do one more 256bit chunk.
-        if (kPaddedInputDimensions != kNumChunks * kSimdWidth * 2)
-        {
-            const auto iv256  = reinterpret_cast<const __m256i*>(&input_vector[kNumChunks]);
-            const auto row256 = reinterpret_cast<const __m256i*>(&row[kNumChunks]);
-  #if defined(USE_VNNI)
-            __m256i product256 = _mm256_dpbusd_epi32(
-                _mm512_castsi512_si256(sum), _mm256_loadA_si256(&iv256[0]), _mm256_load_si256(&row256[0]));
-            sum = _mm512_inserti32x8(sum, product256, 0);
-  #else
-            __m256i product256 = _mm256_maddubs_epi16(_mm256_loadA_si256(&iv256[0]), _mm256_load_si256(&row256[0]));
-            sum = _mm512_add_epi32(sum, _mm512_cvtepi16_epi32(product256));
-  #endif
-        }
-        output[i] = _mm512_reduce_add_epi32(sum) + biases_[i];
-
-  #elif defined(USE_AVX2)
-        __m256i sum = _mm256_setzero_si256();
-        const auto row = reinterpret_cast<const __m256i*>(&weights_[offset]);
-        for (IndexType j = 0; j < kNumChunks; ++j) {
-  #if defined(USE_VNNI)
-          sum = _mm256_dpbusd_epi32(sum, _mm256_loadA_si256(&input_vector[j]), _mm256_load_si256(&row[j]));
-  #else
-          __m256i product = _mm256_maddubs_epi16(_mm256_loadA_si256(&input_vector[j]), _mm256_load_si256(&row[j]));
-          product = _mm256_madd_epi16(product, kOnes);
-          sum = _mm256_add_epi32(sum, product);
-  #endif
-        }
-        __m128i sum128 = _mm_add_epi32(_mm256_castsi256_si128(sum), _mm256_extracti128_si256(sum, 1));
-        sum128 = _mm_add_epi32(sum128, _mm_shuffle_epi32(sum128, _MM_PERM_BADC));
-        sum128 = _mm_add_epi32(sum128, _mm_shuffle_epi32(sum128, _MM_PERM_CDAB));
-        output[i] = _mm_cvtsi128_si32(sum128) + biases_[i];
-
-  #elif defined(USE_SSSE3)
-        __m128i sum = _mm_setzero_si128();
-        const auto row = reinterpret_cast<const __m128i*>(&weights_[offset]);
-        for (int j = 0; j < (int)kNumChunks - 1; j += 2) {
-          __m128i product0 = _mm_maddubs_epi16(_mm_load_si128(&input_vector[j]), _mm_load_si128(&row[j]));
-          product0 = _mm_madd_epi16(product0, kOnes);
-          sum = _mm_add_epi32(sum, product0);
-          __m128i product1 = _mm_maddubs_epi16(_mm_load_si128(&input_vector[j+1]), _mm_load_si128(&row[j+1]));
-          product1 = _mm_madd_epi16(product1, kOnes);
-          sum = _mm_add_epi32(sum, product1);
-        }
-        if (kNumChunks & 0x1) {
-          __m128i product = _mm_maddubs_epi16(_mm_load_si128(&input_vector[kNumChunks-1]), _mm_load_si128(&row[kNumChunks-1]));
-          product = _mm_madd_epi16(product, kOnes);
-          sum = _mm_add_epi32(sum, product);
-        }
-        sum = _mm_add_epi32(sum, _mm_shuffle_epi32(sum, 0x4E)); //_MM_PERM_BADC
-        sum = _mm_add_epi32(sum, _mm_shuffle_epi32(sum, 0xB1)); //_MM_PERM_CDAB
-        output[i] = _mm_cvtsi128_si32(sum) + biases_[i];
-
-  #elif defined(USE_SSE2)
         __m128i sum_lo = _mm_cvtsi32_si128(biases_[i]);
         __m128i sum_hi = kZeros;
         const auto row = reinterpret_cast<const __m128i*>(&weights_[offset]);
         for (IndexType j = 0; j < kNumChunks; ++j) {
           __m128i row_j = _mm_load_si128(&row[j]);
           __m128i input_j = _mm_load_si128(&input_vector[j]);
-          __m128i row_signs = _mm_cmpgt_epi8(kZeros, row_j);
+          __m128i extended_row_lo = _mm_srai_epi16(_mm_unpacklo_epi8(row_j, row_j), 8);
-          __m128i extended_row_lo = _mm_unpacklo_epi8(row_j, row_signs);
+          __m128i extended_row_hi = _mm_srai_epi16(_mm_unpackhi_epi8(row_j, row_j), 8);
-          __m128i extended_row_hi = _mm_unpackhi_epi8(row_j, row_signs);
           __m128i extended_input_lo = _mm_unpacklo_epi8(input_j, kZeros);
           __m128i extended_input_hi = _mm_unpackhi_epi8(input_j, kZeros);
           __m128i product_lo = _mm_madd_epi16(extended_row_lo, extended_input_lo);
@@ -204,16 +384,15 @@ namespace Eval::NNUE::Layers {
         sum = _mm_add_epi32(sum, sum_second_32);
         output[i] = _mm_cvtsi128_si32(sum);
 
-  #elif defined(USE_MMX)
+#elif defined(USE_MMX)
         __m64 sum_lo = _mm_cvtsi32_si64(biases_[i]);
         __m64 sum_hi = kZeros;
         const auto row = reinterpret_cast<const __m64*>(&weights_[offset]);
         for (IndexType j = 0; j < kNumChunks; ++j) {
           __m64 row_j = row[j];
           __m64 input_j = input_vector[j];
-          __m64 row_signs = _mm_cmpgt_pi8(kZeros, row_j);
+          __m64 extended_row_lo = _mm_srai_pi16(_mm_unpacklo_pi8(row_j, row_j), 8);
-          __m64 extended_row_lo = _mm_unpacklo_pi8(row_j, row_signs);
+          __m64 extended_row_hi = _mm_srai_pi16(_mm_unpackhi_pi8(row_j, row_j), 8);
-          __m64 extended_row_hi = _mm_unpackhi_pi8(row_j, row_signs);
           __m64 extended_input_lo = _mm_unpacklo_pi8(input_j, kZeros);
           __m64 extended_input_hi = _mm_unpackhi_pi8(input_j, kZeros);
           __m64 product_lo = _mm_madd_pi16(extended_row_lo, extended_input_lo);
@@ -225,7 +404,7 @@ namespace Eval::NNUE::Layers {
         sum = _mm_add_pi32(sum, _mm_unpackhi_pi32(sum, sum));
         output[i] = _mm_cvtsi64_si32(sum);
 
-  #elif defined(USE_NEON)
+#elif defined(USE_NEON)
         int32x4_t sum = {biases_[i]};
         const auto row = reinterpret_cast<const int8x8_t*>(&weights_[offset]);
         for (IndexType j = 0; j < kNumChunks; ++j) {
@@ -235,18 +414,21 @@ namespace Eval::NNUE::Layers {
         }
         output[i] = sum[0] + sum[1] + sum[2] + sum[3];
 
-  #else
+#else
         OutputType sum = biases_[i];
         for (IndexType j = 0; j < kInputDimensions; ++j) {
           sum += weights_[offset + j] * input[j];
         }
         output[i] = sum;
-  #endif
+#endif
 
       }
-  #if defined(USE_MMX)
+#if defined(USE_MMX)
       _mm_empty();
-  #endif
+#endif
+
+#endif
+
       return output;
     }
 
@@ -257,8 +439,24 @@ namespace Eval::NNUE::Layers {
     PreviousLayer previous_layer_;
 
     alignas(kCacheLineSize) BiasType biases_[kOutputDimensions];
-    alignas(kCacheLineSize)
+    alignas(kCacheLineSize) WeightType weights_[kOutputDimensions * kPaddedInputDimensions];
-        WeightType weights_[kOutputDimensions * kPaddedInputDimensions];
+#if defined (USE_SSSE3)
+    struct CanSaturate {
+        int count;
+        struct Entry {
+            uint16_t out;
+            uint16_t in;
+            int8_t w;
+        } ids[kPaddedInputDimensions * kOutputDimensions * 3 / 4];
+
+        void add(int i, int j, int8_t w) {
+            ids[count].out = i;
+            ids[count].in = j;
+            ids[count].w = w;
+            ++count;
+        }
+    } canSaturate16;
+#endif
   };
 
 }  // namespace Eval::NNUE::Layers

DroidFishApp/src/main/cpp/stockfish/nnue/layers/clipped_relu.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -74,12 +74,12 @@ namespace Eval::NNUE::Layers {
       const auto out = reinterpret_cast<__m256i*>(output);
       for (IndexType i = 0; i < kNumChunks; ++i) {
         const __m256i words0 = _mm256_srai_epi16(_mm256_packs_epi32(
-            _mm256_loadA_si256(&in[i * 4 + 0]),
+            _mm256_load_si256(&in[i * 4 + 0]),
-            _mm256_loadA_si256(&in[i * 4 + 1])), kWeightScaleBits);
+            _mm256_load_si256(&in[i * 4 + 1])), kWeightScaleBits);
         const __m256i words1 = _mm256_srai_epi16(_mm256_packs_epi32(
-            _mm256_loadA_si256(&in[i * 4 + 2]),
+            _mm256_load_si256(&in[i * 4 + 2]),
-            _mm256_loadA_si256(&in[i * 4 + 3])), kWeightScaleBits);
+            _mm256_load_si256(&in[i * 4 + 3])), kWeightScaleBits);
-        _mm256_storeA_si256(&out[i], _mm256_permutevar8x32_epi32(_mm256_max_epi8(
+        _mm256_store_si256(&out[i], _mm256_permutevar8x32_epi32(_mm256_max_epi8(
             _mm256_packs_epi16(words0, words1), kZero), kOffsets));
       }
       constexpr IndexType kStart = kNumChunks * kSimdWidth;

DroidFishApp/src/main/cpp/stockfish/nnue/layers/input_slice.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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

DroidFishApp/src/main/cpp/stockfish/nnue/nnue_accumulator.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -25,11 +25,14 @@
 
 namespace Eval::NNUE {
 
+  // The accumulator of a StateInfo without parent is set to the INIT state
+  enum AccumulatorState { EMPTY, COMPUTED, INIT };
+
   // Class that holds the result of affine transformation of input features
   struct alignas(kCacheLineSize) Accumulator {
     std::int16_t
         accumulation[2][kRefreshTriggers.size()][kTransformedFeatureDimensions];
-    bool computed_accumulation;
+    AccumulatorState state[2];
   };
 
 }  // namespace Eval::NNUE

DroidFishApp/src/main/cpp/stockfish/nnue/nnue_architecture.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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

DroidFishApp/src/main/cpp/stockfish/nnue/nnue_common.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -43,29 +43,6 @@
 #include <arm_neon.h>
 #endif
 
-// HACK: Use _mm256_loadu_si256() instead of _mm256_load_si256. Otherwise a binary
-//       compiled with older g++ crashes because the output memory is not aligned
-//       even though alignas is specified.
-#if defined(USE_AVX2)
-#if defined(__GNUC__ ) && (__GNUC__ < 9) && defined(_WIN32) && !defined(__clang__)
-#define _mm256_loadA_si256  _mm256_loadu_si256
-#define _mm256_storeA_si256 _mm256_storeu_si256
-#else
-#define _mm256_loadA_si256  _mm256_load_si256
-#define _mm256_storeA_si256 _mm256_store_si256
-#endif
-#endif
-
-#if defined(USE_AVX512)
-#if defined(__GNUC__ ) && (__GNUC__ < 9) && defined(_WIN32) && !defined(__clang__)
-#define _mm512_loadA_si512   _mm512_loadu_si512
-#define _mm512_storeA_si512  _mm512_storeu_si512
-#else
-#define _mm512_loadA_si512   _mm512_load_si512
-#define _mm512_storeA_si512  _mm512_store_si512
-#endif
-#endif
-
 namespace Eval::NNUE {
 
   // Version of the evaluation file
@@ -113,7 +90,14 @@ namespace Eval::NNUE {
     PS_END2     = 12 * SQUARE_NB + 1
   };
 
-  extern const uint32_t kpp_board_index[PIECE_NB][COLOR_NB];
+  constexpr uint32_t kpp_board_index[COLOR_NB][PIECE_NB] = {
+    // convention: W - us, B - them
+    // viewed from other side, W and B are reversed
+    { PS_NONE, PS_W_PAWN, PS_W_KNIGHT, PS_W_BISHOP, PS_W_ROOK, PS_W_QUEEN, PS_W_KING, PS_NONE,
+      PS_NONE, PS_B_PAWN, PS_B_KNIGHT, PS_B_BISHOP, PS_B_ROOK, PS_B_QUEEN, PS_B_KING, PS_NONE },
+    { PS_NONE, PS_B_PAWN, PS_B_KNIGHT, PS_B_BISHOP, PS_B_ROOK, PS_B_QUEEN, PS_B_KING, PS_NONE,
+      PS_NONE, PS_W_PAWN, PS_W_KNIGHT, PS_W_BISHOP, PS_W_ROOK, PS_W_QUEEN, PS_W_KING, PS_NONE }
+  };
 
   // Type of input feature after conversion
   using TransformedFeatureType = std::uint8_t;

DroidFishApp/src/main/cpp/stockfish/nnue/nnue_feature_transformer.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -32,20 +32,20 @@ namespace Eval::NNUE {
   // If vector instructions are enabled, we update and refresh the
   // accumulator tile by tile such that each tile fits in the CPU's
   // vector registers.
-  #define TILING
+  #define VECTOR
 
   #ifdef USE_AVX512
   typedef __m512i vec_t;
-  #define vec_load(a) _mm512_loadA_si512(a)
+  #define vec_load(a) _mm512_load_si512(a)
-  #define vec_store(a,b) _mm512_storeA_si512(a,b)
+  #define vec_store(a,b) _mm512_store_si512(a,b)
   #define vec_add_16(a,b) _mm512_add_epi16(a,b)
   #define vec_sub_16(a,b) _mm512_sub_epi16(a,b)
   static constexpr IndexType kNumRegs = 8; // only 8 are needed
 
   #elif USE_AVX2
   typedef __m256i vec_t;
-  #define vec_load(a) _mm256_loadA_si256(a)
+  #define vec_load(a) _mm256_load_si256(a)
-  #define vec_store(a,b) _mm256_storeA_si256(a,b)
+  #define vec_store(a,b) _mm256_store_si256(a,b)
   #define vec_add_16(a,b) _mm256_add_epi16(a,b)
   #define vec_sub_16(a,b) _mm256_sub_epi16(a,b)
   static constexpr IndexType kNumRegs = 16;
@@ -75,7 +75,7 @@ namespace Eval::NNUE {
   static constexpr IndexType kNumRegs = 16;
 
   #else
-  #undef TILING
+  #undef VECTOR
 
   #endif
 
@@ -86,7 +86,7 @@ namespace Eval::NNUE {
     // Number of output dimensions for one side
     static constexpr IndexType kHalfDimensions = kTransformedFeatureDimensions;
 
-    #ifdef TILING
+    #ifdef VECTOR
     static constexpr IndexType kTileHeight = kNumRegs * sizeof(vec_t) / 2;
     static_assert(kHalfDimensions % kTileHeight == 0, "kTileHeight must divide kHalfDimensions");
     #endif
@@ -119,36 +119,21 @@ namespace Eval::NNUE {
       return !stream.fail();
     }
 
-    // Proceed with the difference calculation if possible
-    bool UpdateAccumulatorIfPossible(const Position& pos) const {
-
-      const auto now = pos.state();
-      if (now->accumulator.computed_accumulation)
-        return true;
-
-      const auto prev = now->previous;
-      if (prev) {
-        if (prev->accumulator.computed_accumulation) {
-          UpdateAccumulator(pos);
-          return true;
-        } else if (prev->previous && prev->previous->accumulator.computed_accumulation) {
-          UpdateAccumulator(pos);
-          return true;
-        }
-      }
-
-      return false;
-    }
-
     // Convert input features
     void Transform(const Position& pos, OutputType* output) const {
 
-      if (!UpdateAccumulatorIfPossible(pos))
+      UpdateAccumulator(pos, WHITE);
-        RefreshAccumulator(pos);
+      UpdateAccumulator(pos, BLACK);
 
       const auto& accumulation = pos.state()->accumulator.accumulation;
 
-  #if defined(USE_AVX2)
+  #if defined(USE_AVX512)
+      constexpr IndexType kNumChunks = kHalfDimensions / (kSimdWidth * 2);
+      static_assert(kHalfDimensions % (kSimdWidth * 2) == 0);
+      const __m512i kControl = _mm512_setr_epi64(0, 2, 4, 6, 1, 3, 5, 7);
+      const __m512i kZero = _mm512_setzero_si512();
+
+  #elif defined(USE_AVX2)
       constexpr IndexType kNumChunks = kHalfDimensions / kSimdWidth;
       constexpr int kControl = 0b11011000;
       const __m256i kZero = _mm256_setzero_si256();
@@ -175,14 +160,25 @@ namespace Eval::NNUE {
       for (IndexType p = 0; p < 2; ++p) {
         const IndexType offset = kHalfDimensions * p;
 
-  #if defined(USE_AVX2)
+  #if defined(USE_AVX512)
+        auto out = reinterpret_cast<__m512i*>(&output[offset]);
+        for (IndexType j = 0; j < kNumChunks; ++j) {
+          __m512i sum0 = _mm512_load_si512(
+              &reinterpret_cast<const __m512i*>(accumulation[perspectives[p]][0])[j * 2 + 0]);
+          __m512i sum1 = _mm512_load_si512(
+              &reinterpret_cast<const __m512i*>(accumulation[perspectives[p]][0])[j * 2 + 1]);
+          _mm512_store_si512(&out[j], _mm512_permutexvar_epi64(kControl,
+              _mm512_max_epi8(_mm512_packs_epi16(sum0, sum1), kZero)));
+        }
+
+  #elif defined(USE_AVX2)
         auto out = reinterpret_cast<__m256i*>(&output[offset]);
         for (IndexType j = 0; j < kNumChunks; ++j) {
-          __m256i sum0 = _mm256_loadA_si256(
+          __m256i sum0 = _mm256_load_si256(
               &reinterpret_cast<const __m256i*>(accumulation[perspectives[p]][0])[j * 2 + 0]);
-          __m256i sum1 = _mm256_loadA_si256(
+          __m256i sum1 = _mm256_load_si256(
-            &reinterpret_cast<const __m256i*>(accumulation[perspectives[p]][0])[j * 2 + 1]);
+              &reinterpret_cast<const __m256i*>(accumulation[perspectives[p]][0])[j * 2 + 1]);
-          _mm256_storeA_si256(&out[j], _mm256_permute4x64_epi64(_mm256_max_epi8(
+          _mm256_store_si256(&out[j], _mm256_permute4x64_epi64(_mm256_max_epi8(
               _mm256_packs_epi16(sum0, sum1), kZero), kControl));
         }
 
@@ -198,9 +194,9 @@ namespace Eval::NNUE {
           _mm_store_si128(&out[j],
 
   #ifdef USE_SSE41
-            _mm_max_epi8(packedbytes, kZero)
+              _mm_max_epi8(packedbytes, kZero)
   #else
-            _mm_subs_epi8(_mm_adds_epi8(packedbytes, k0x80s), k0x80s)
+              _mm_subs_epi8(_mm_adds_epi8(packedbytes, k0x80s), k0x80s)
   #endif
 
           );
@@ -240,27 +236,142 @@ namespace Eval::NNUE {
     }
 
    private:
-    // Calculate cumulative value without using difference calculation
+    void UpdateAccumulator(const Position& pos, const Color c) const {
-    void RefreshAccumulator(const Position& pos) const {
 
-      auto& accumulator = pos.state()->accumulator;
+  #ifdef VECTOR
-      IndexType i = 0;
+      // Gcc-10.2 unnecessarily spills AVX2 registers if this array
-      Features::IndexList active_indices[2];
+      // is defined in the VECTOR code below, once in each branch
-      RawFeatures::AppendActiveIndices(pos, kRefreshTriggers[i],
+      vec_t acc[kNumRegs];
-                                       active_indices);
+  #endif
-      for (Color perspective : { WHITE, BLACK }) {
+
-  #ifdef TILING
+      // Look for a usable accumulator of an earlier position. We keep track
-        for (unsigned j = 0; j < kHalfDimensions / kTileHeight; ++j) {
+      // of the estimated gain in terms of features to be added/subtracted.
+      StateInfo *st = pos.state(), *next = nullptr;
+      int gain = pos.count<ALL_PIECES>() - 2;
+      while (st->accumulator.state[c] == EMPTY)
+      {
+        auto& dp = st->dirtyPiece;
+        // The first condition tests whether an incremental update is
+        // possible at all: if this side's king has moved, it is not possible.
+        static_assert(std::is_same_v<RawFeatures::SortedTriggerSet,
+              Features::CompileTimeList<Features::TriggerEvent, Features::TriggerEvent::kFriendKingMoved>>,
+              "Current code assumes that only kFriendlyKingMoved refresh trigger is being used.");
+        if (   dp.piece[0] == make_piece(c, KING)
+            || (gain -= dp.dirty_num + 1) < 0)
+          break;
+        next = st;
+        st = st->previous;
+      }
+
+      if (st->accumulator.state[c] == COMPUTED)
+      {
+        if (next == nullptr)
+          return;
+
+        // Update incrementally in two steps. First, we update the "next"
+        // accumulator. Then, we update the current accumulator (pos.state()).
+
+        // Gather all features to be updated. This code assumes HalfKP features
+        // only and doesn't support refresh triggers.
+        static_assert(std::is_same_v<Features::FeatureSet<Features::HalfKP<Features::Side::kFriend>>,
+                                     RawFeatures>);
+        Features::IndexList removed[2], added[2];
+        Features::HalfKP<Features::Side::kFriend>::AppendChangedIndices(pos,
+            next->dirtyPiece, c, &removed[0], &added[0]);
+        for (StateInfo *st2 = pos.state(); st2 != next; st2 = st2->previous)
+          Features::HalfKP<Features::Side::kFriend>::AppendChangedIndices(pos,
+              st2->dirtyPiece, c, &removed[1], &added[1]);
+
+        // Mark the accumulators as computed.
+        next->accumulator.state[c] = COMPUTED;
+        pos.state()->accumulator.state[c] = COMPUTED;
+
+        // Now update the accumulators listed in info[], where the last element is a sentinel.
+        StateInfo *info[3] =
+          { next, next == pos.state() ? nullptr : pos.state(), nullptr };
+  #ifdef VECTOR
+        for (IndexType j = 0; j < kHalfDimensions / kTileHeight; ++j)
+        {
+          // Load accumulator
+          auto accTile = reinterpret_cast<vec_t*>(
+            &st->accumulator.accumulation[c][0][j * kTileHeight]);
+          for (IndexType k = 0; k < kNumRegs; ++k)
+            acc[k] = vec_load(&accTile[k]);
+
+          for (IndexType i = 0; info[i]; ++i)
+          {
+            // Difference calculation for the deactivated features
+            for (const auto index : removed[i])
+            {
+              const IndexType offset = kHalfDimensions * index + j * kTileHeight;
+              auto column = reinterpret_cast<const vec_t*>(&weights_[offset]);
+              for (IndexType k = 0; k < kNumRegs; ++k)
+                acc[k] = vec_sub_16(acc[k], column[k]);
+            }
+
+            // Difference calculation for the activated features
+            for (const auto index : added[i])
+            {
+              const IndexType offset = kHalfDimensions * index + j * kTileHeight;
+              auto column = reinterpret_cast<const vec_t*>(&weights_[offset]);
+              for (IndexType k = 0; k < kNumRegs; ++k)
+                acc[k] = vec_add_16(acc[k], column[k]);
+            }
+
+            // Store accumulator
+            accTile = reinterpret_cast<vec_t*>(
+              &info[i]->accumulator.accumulation[c][0][j * kTileHeight]);
+            for (IndexType k = 0; k < kNumRegs; ++k)
+              vec_store(&accTile[k], acc[k]);
+          }
+        }
+
+  #else
+        for (IndexType i = 0; info[i]; ++i)
+        {
+          std::memcpy(info[i]->accumulator.accumulation[c][0],
+              st->accumulator.accumulation[c][0],
+              kHalfDimensions * sizeof(BiasType));
+          st = info[i];
+
+          // Difference calculation for the deactivated features
+          for (const auto index : removed[i])
+          {
+            const IndexType offset = kHalfDimensions * index;
+
+            for (IndexType j = 0; j < kHalfDimensions; ++j)
+              st->accumulator.accumulation[c][0][j] -= weights_[offset + j];
+          }
+
+          // Difference calculation for the activated features
+          for (const auto index : added[i])
+          {
+            const IndexType offset = kHalfDimensions * index;
+
+            for (IndexType j = 0; j < kHalfDimensions; ++j)
+              st->accumulator.accumulation[c][0][j] += weights_[offset + j];
+          }
+        }
+  #endif
+      }
+      else
+      {
+        // Refresh the accumulator
+        auto& accumulator = pos.state()->accumulator;
+        accumulator.state[c] = COMPUTED;
+        Features::IndexList active;
+        Features::HalfKP<Features::Side::kFriend>::AppendActiveIndices(pos, c, &active);
+
+  #ifdef VECTOR
+        for (IndexType j = 0; j < kHalfDimensions / kTileHeight; ++j)
+        {
           auto biasesTile = reinterpret_cast<const vec_t*>(
               &biases_[j * kTileHeight]);
-          auto accTile = reinterpret_cast<vec_t*>(
+          for (IndexType k = 0; k < kNumRegs; ++k)
-              &accumulator.accumulation[perspective][i][j * kTileHeight]);
-          vec_t acc[kNumRegs];
-
-          for (unsigned k = 0; k < kNumRegs; ++k)
             acc[k] = biasesTile[k];
 
-          for (const auto index : active_indices[perspective]) {
+          for (const auto index : active)
+          {
             const IndexType offset = kHalfDimensions * index + j * kTileHeight;
             auto column = reinterpret_cast<const vec_t*>(&weights_[offset]);
 
@@ -268,18 +379,22 @@ namespace Eval::NNUE {
               acc[k] = vec_add_16(acc[k], column[k]);
           }
 
+          auto accTile = reinterpret_cast<vec_t*>(
+              &accumulator.accumulation[c][0][j * kTileHeight]);
           for (unsigned k = 0; k < kNumRegs; k++)
             vec_store(&accTile[k], acc[k]);
         }
+
   #else
-        std::memcpy(accumulator.accumulation[perspective][i], biases_,
+        std::memcpy(accumulator.accumulation[c][0], biases_,
             kHalfDimensions * sizeof(BiasType));
 
-        for (const auto index : active_indices[perspective]) {
+        for (const auto index : active)
+        {
           const IndexType offset = kHalfDimensions * index;
 
           for (IndexType j = 0; j < kHalfDimensions; ++j)
-            accumulator.accumulation[perspective][i][j] += weights_[offset + j];
+            accumulator.accumulation[c][0][j] += weights_[offset + j];
         }
   #endif
       }
@@ -287,106 +402,6 @@ namespace Eval::NNUE {
   #if defined(USE_MMX)
       _mm_empty();
   #endif
-
-      accumulator.computed_accumulation = true;
-    }
-
-    // Calculate cumulative value using difference calculation
-    void UpdateAccumulator(const Position& pos) const {
-
-      Accumulator* prev_accumulator;
-      assert(pos.state()->previous);
-      if (pos.state()->previous->accumulator.computed_accumulation) {
-        prev_accumulator = &pos.state()->previous->accumulator;
-      }
-      else {
-        assert(pos.state()->previous->previous);
-        assert(pos.state()->previous->previous->accumulator.computed_accumulation);
-        prev_accumulator = &pos.state()->previous->previous->accumulator;
-      }
-
-      auto& accumulator = pos.state()->accumulator;
-      IndexType i = 0;
-      Features::IndexList removed_indices[2], added_indices[2];
-      bool reset[2] = { false, false };
-      RawFeatures::AppendChangedIndices(pos, kRefreshTriggers[i],
-                                        removed_indices, added_indices, reset);
-
-  #ifdef TILING
-      for (IndexType j = 0; j < kHalfDimensions / kTileHeight; ++j) {
-        for (Color perspective : { WHITE, BLACK }) {
-          auto accTile = reinterpret_cast<vec_t*>(
-              &accumulator.accumulation[perspective][i][j * kTileHeight]);
-          vec_t acc[kNumRegs];
-
-          if (reset[perspective]) {
-            auto biasesTile = reinterpret_cast<const vec_t*>(
-                &biases_[j * kTileHeight]);
-            for (unsigned k = 0; k < kNumRegs; ++k)
-              acc[k] = biasesTile[k];
-          } else {
-            auto prevAccTile = reinterpret_cast<const vec_t*>(
-                &prev_accumulator->accumulation[perspective][i][j * kTileHeight]);
-            for (IndexType k = 0; k < kNumRegs; ++k)
-              acc[k] = vec_load(&prevAccTile[k]);
-
-            // Difference calculation for the deactivated features
-            for (const auto index : removed_indices[perspective]) {
-              const IndexType offset = kHalfDimensions * index + j * kTileHeight;
-              auto column = reinterpret_cast<const vec_t*>(&weights_[offset]);
-
-              for (IndexType k = 0; k < kNumRegs; ++k)
-                acc[k] = vec_sub_16(acc[k], column[k]);
-            }
-          }
-          { // Difference calculation for the activated features
-            for (const auto index : added_indices[perspective]) {
-              const IndexType offset = kHalfDimensions * index + j * kTileHeight;
-              auto column = reinterpret_cast<const vec_t*>(&weights_[offset]);
-
-              for (IndexType k = 0; k < kNumRegs; ++k)
-                acc[k] = vec_add_16(acc[k], column[k]);
-            }
-          }
-
-          for (IndexType k = 0; k < kNumRegs; ++k)
-            vec_store(&accTile[k], acc[k]);
-        }
-      }
-  #if defined(USE_MMX)
-      _mm_empty();
-  #endif
-
-  #else
-      for (Color perspective : { WHITE, BLACK }) {
-
-        if (reset[perspective]) {
-          std::memcpy(accumulator.accumulation[perspective][i], biases_,
-                      kHalfDimensions * sizeof(BiasType));
-        } else {
-          std::memcpy(accumulator.accumulation[perspective][i],
-                      prev_accumulator->accumulation[perspective][i],
-                      kHalfDimensions * sizeof(BiasType));
-          // Difference calculation for the deactivated features
-          for (const auto index : removed_indices[perspective]) {
-            const IndexType offset = kHalfDimensions * index;
-
-            for (IndexType j = 0; j < kHalfDimensions; ++j)
-              accumulator.accumulation[perspective][i][j] -= weights_[offset + j];
-          }
-        }
-        { // Difference calculation for the activated features
-          for (const auto index : added_indices[perspective]) {
-            const IndexType offset = kHalfDimensions * index;
-
-            for (IndexType j = 0; j < kHalfDimensions; ++j)
-              accumulator.accumulation[perspective][i][j] += weights_[offset + j];
-          }
-        }
-      }
-  #endif
-
-      accumulator.computed_accumulation = true;
     }
 
     using BiasType = std::int16_t;

DroidFishApp/src/main/cpp/stockfish/pawns.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -30,29 +30,30 @@ namespace {
   #define S(mg, eg) make_score(mg, eg)
 
   // Pawn penalties
-  constexpr Score Backward      = S( 8, 27);
+  constexpr Score Backward      = S( 9, 22);
-  constexpr Score Doubled       = S(11, 55);
+  constexpr Score Doubled       = S(13, 51);
-  constexpr Score Isolated      = S( 5, 17);
+  constexpr Score DoubledEarly  = S(20,  7);
-  constexpr Score WeakLever     = S( 2, 54);
+  constexpr Score Isolated      = S( 3, 15);
-  constexpr Score WeakUnopposed = S(15, 25);
+  constexpr Score WeakLever     = S( 4, 58);
+  constexpr Score WeakUnopposed = S(13, 24);
 
   // Bonus for blocked pawns at 5th or 6th rank
-  constexpr Score BlockedPawn[2] = { S(-13, -4), S(-4, 3) };
+  constexpr Score BlockedPawn[2] = { S(-17, -6), S(-9, 2) };
 
   constexpr Score BlockedStorm[RANK_NB] = {
-    S(0, 0), S(0, 0), S(76, 78), S(-10, 15), S(-7, 10), S(-4, 6), S(-1, 2)
+    S(0, 0), S(0, 0), S(75, 78), S(-8, 16), S(-6, 10), S(-6, 6), S(0, 2)
   };
 
   // Connected pawn bonus
-  constexpr int Connected[RANK_NB] = { 0, 7, 8, 11, 24, 45, 85 };
+  constexpr int Connected[RANK_NB] = { 0, 5, 7, 11, 23, 48, 87 };
 
   // Strength of pawn shelter for our king by [distance from edge][rank].
   // RANK_1 = 0 is used for files where we have no pawn, or pawn is behind our king.
   constexpr Value ShelterStrength[int(FILE_NB) / 2][RANK_NB] = {
-    { V( -6), V( 81), V( 93), V( 58), V( 39), V( 18), V(  25) },
+    { V( -5), V( 82), V( 92), V( 54), V( 36), V( 22), V(  28) },
-    { V(-43), V( 61), V( 35), V(-49), V(-29), V(-11), V( -63) },
+    { V(-44), V( 63), V( 33), V(-50), V(-30), V(-12), V( -62) },
-    { V(-10), V( 75), V( 23), V( -2), V( 32), V(  3), V( -45) },
+    { V(-11), V( 77), V( 22), V( -6), V( 31), V(  8), V( -45) },
-    { V(-39), V(-13), V(-29), V(-52), V(-48), V(-67), V(-166) }
+    { V(-39), V(-12), V(-29), V(-50), V(-43), V(-68), V(-164) }
   };
 
   // Danger of enemy pawns moving toward our king by [distance from edge][rank].
@@ -60,12 +61,18 @@ namespace {
   // is behind our king. Note that UnblockedStorm[0][1-2] accommodate opponent pawn
   // on edge, likely blocked by our king.
   constexpr Value UnblockedStorm[int(FILE_NB) / 2][RANK_NB] = {
-    { V( 85), V(-289), V(-166), V(97), V(50), V( 45), V( 50) },
+    { V( 87), V(-288), V(-168), V( 96), V( 47), V( 44), V( 46) },
-    { V( 46), V( -25), V( 122), V(45), V(37), V(-10), V( 20) },
+    { V( 42), V( -25), V( 120), V( 45), V( 34), V( -9), V( 24) },
-    { V( -6), V(  51), V( 168), V(34), V(-2), V(-22), V(-14) },
+    { V( -8), V(  51), V( 167), V( 35), V( -4), V(-16), V(-12) },
-    { V(-15), V( -11), V( 101), V( 4), V(11), V(-15), V(-29) }
+    { V(-17), V( -13), V( 100), V(  4), V(  9), V(-16), V(-31) }
   };
 
+
+  // KingOnFile[semi-open Us][semi-open Them] contains bonuses/penalties
+  // for king when the king is on a semi-open or open file.
+  constexpr Score KingOnFile[2][2] = {{ S(-21,10), S(-7, 1)  },
+                                     {  S(  0,-3), S( 9,-4) }};
+
   #undef S
   #undef V
 
@@ -80,13 +87,14 @@ namespace {
 
     constexpr Color     Them = ~Us;
     constexpr Direction Up   = pawn_push(Us);
+    constexpr Direction Down = -Up;
 
     Bitboard neighbours, stoppers, support, phalanx, opposed;
     Bitboard lever, leverPush, blocked;
     Square s;
     bool backward, passed, doubled;
     Score score = SCORE_ZERO;
-    const Square* pl = pos.squares<PAWN>(Us);
+    Bitboard b = pos.pieces(Us, PAWN);
 
     Bitboard ourPawns   = pos.pieces(  Us, PAWN);
     Bitboard theirPawns = pos.pieces(Them, PAWN);
@@ -99,8 +107,9 @@ namespace {
     e->blockedCount += popcount(shift<Up>(ourPawns) & (theirPawns | doubleAttackThem));
 
     // Loop through all pawns of the current color and score each pawn
-    while ((s = *pl++) != SQ_NONE)
+    while (b) {
-    {
+        s = pop_lsb(&b);
+
         assert(pos.piece_on(s) == make_piece(Us, PAWN));
 
         Rank r = relative_rank(Us, s);
@@ -116,6 +125,13 @@ namespace {
         phalanx    = neighbours & rank_bb(s);
         support    = neighbours & rank_bb(s - Up);
 
+        if (doubled)
+        {
+            // Additional doubled penalty if none of their pawns is fixed
+            if (!(ourPawns & shift<Down>(theirPawns | pawn_attacks_bb<Them>(theirPawns))))
+                score -= DoubledEarly;
+        }
+
         // A pawn is backward when it is behind all pawns of the same color on
         // the adjacent files and cannot safely advance.
         backward =  !(neighbours & forward_ranks_bb(Them, s + Up))
@@ -147,7 +163,7 @@ namespace {
         if (support | phalanx)
         {
             int v =  Connected[r] * (2 + bool(phalanx) - bool(opposed))
-                   + 21 * popcount(support);
+                   + 22 * popcount(support);
 
             score += make_score(v, v * (r - 2) / 4);
         }
@@ -165,14 +181,14 @@ namespace {
 
         else if (backward)
             score -=  Backward
-                    + WeakUnopposed * !opposed;
+                    + WeakUnopposed * !opposed * bool(~(FileABB | FileHBB) & s);
 
         if (!support)
             score -=  Doubled * doubled
                     + WeakLever * more_than_one(lever);
 
-        if (blocked && r > RANK_4)
+        if (blocked && r >= RANK_5)
-            score += BlockedPawn[r-4];
+            score += BlockedPawn[r - RANK_5];
     }
 
     return score;
@@ -237,6 +253,9 @@ Score Entry::evaluate_shelter(const Position& pos, Square ksq) const {
           bonus -= make_score(UnblockedStorm[d][theirRank], 0);
   }
 
+  // King On File
+  bonus -= KingOnFile[pos.is_on_semiopen_file(Us, ksq)][pos.is_on_semiopen_file(Them, ksq)];
+
   return bonus;
 }
 

DroidFishApp/src/main/cpp/stockfish/pawns.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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

DroidFishApp/src/main/cpp/stockfish/position.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -77,6 +77,8 @@ std::ostream& operator<<(std::ostream& os, const Position& pos) {
       && !pos.can_castle(ANY_CASTLING))
   {
       StateInfo st;
+      ASSERT_ALIGNED(&st, Eval::NNUE::kCacheLineSize);
+
       Position p;
       p.set(pos.fen(), pos.is_chess960(), &st, pos.this_thread());
       Tablebases::ProbeState s1, s2;
@@ -195,7 +197,6 @@ Position& Position::set(const string& fenStr, bool isChess960, StateInfo* si, Th
 
   std::memset(this, 0, sizeof(Position));
   std::memset(si, 0, sizeof(StateInfo));
-  std::fill_n(&pieceList[0][0], sizeof(pieceList) / sizeof(Square), SQ_NONE);
   st = si;
 
   ss >> std::noskipws;
@@ -248,6 +249,8 @@ Position& Position::set(const string& fenStr, bool isChess960, StateInfo* si, Th
       set_castling_right(c, rsq);
   }
 
+  set_state(st);
+
   // 4. En passant square.
   // Ignore if square is invalid or not on side to move relative rank 6.
   bool enpassant = false;
@@ -261,12 +264,24 @@ Position& Position::set(const string& fenStr, bool isChess960, StateInfo* si, Th
       // a) side to move have a pawn threatening epSquare
       // b) there is an enemy pawn in front of epSquare
       // c) there is no piece on epSquare or behind epSquare
+      // d) enemy pawn didn't block a check of its own color by moving forward
       enpassant = pawn_attacks_bb(~sideToMove, st->epSquare) & pieces(sideToMove, PAWN)
                && (pieces(~sideToMove, PAWN) & (st->epSquare + pawn_push(~sideToMove)))
-               && !(pieces() & (st->epSquare | (st->epSquare + pawn_push(sideToMove))));
+               && !(pieces() & (st->epSquare | (st->epSquare + pawn_push(sideToMove))))
+               && (   file_of(square<KING>(sideToMove)) == file_of(st->epSquare)
+                   || !(blockers_for_king(sideToMove) & (st->epSquare + pawn_push(~sideToMove))));
   }
 
-  if (!enpassant)
+  // It's necessary for st->previous to be intialized in this way because legality check relies on its existence
+  if (enpassant) {
+      st->previous = new StateInfo();
+      remove_piece(st->epSquare - pawn_push(sideToMove));
+      st->previous->checkersBB = attackers_to(square<KING>(~sideToMove)) & pieces(sideToMove);
+      st->previous->blockersForKing[WHITE] = slider_blockers(pieces(BLACK), square<KING>(WHITE), st->previous->pinners[BLACK]);
+      st->previous->blockersForKing[BLACK] = slider_blockers(pieces(WHITE), square<KING>(BLACK), st->previous->pinners[WHITE]);
+      put_piece(make_piece(~sideToMove, PAWN), st->epSquare - pawn_push(sideToMove));
+  }
+  else
       st->epSquare = SQ_NONE;
 
   // 5-6. Halfmove clock and fullmove number
@@ -278,7 +293,8 @@ Position& Position::set(const string& fenStr, bool isChess960, StateInfo* si, Th
 
   chess960 = isChess960;
   thisThread = th;
-  set_state(st);
+  st->accumulator.state[WHITE] = Eval::NNUE::INIT;
+  st->accumulator.state[BLACK] = Eval::NNUE::INIT;
 
   assert(pos_is_ok());
 
@@ -499,23 +515,11 @@ bool Position::legal(Move m) const {
   assert(color_of(moved_piece(m)) == us);
   assert(piece_on(square<KING>(us)) == make_piece(us, KING));
 
-  // En passant captures are a tricky special case. Because they are rather
+  // st->previous->blockersForKing consider capsq as empty.
-  // uncommon, we do it simply by testing whether the king is attacked after
+  // If pinned, it has to move along the king ray.
-  // the move is made.
+  if (type_of(m) == EN_PASSANT)
-  if (type_of(m) == ENPASSANT)
+      return   !(st->previous->blockersForKing[sideToMove] & from)
-  {
+            || aligned(from, to, square<KING>(us));
-      Square ksq = square<KING>(us);
-      Square capsq = to - pawn_push(us);
-      Bitboard occupied = (pieces() ^ from ^ capsq) | to;
-
-      assert(to == ep_square());
-      assert(moved_piece(m) == make_piece(us, PAWN));
-      assert(piece_on(capsq) == make_piece(~us, PAWN));
-      assert(piece_on(to) == NO_PIECE);
-
-      return   !(attacks_bb<  ROOK>(ksq, occupied) & pieces(~us, QUEEN, ROOK))
-            && !(attacks_bb<BISHOP>(ksq, occupied) & pieces(~us, QUEEN, BISHOP));
-  }
 
   // Castling moves generation does not check if the castling path is clear of
   // enemy attacks, it is delayed at a later time: now!
@@ -530,11 +534,9 @@ bool Position::legal(Move m) const {
           if (attackers_to(s) & pieces(~us))
               return false;
 
-      // In case of Chess960, verify that when moving the castling rook we do
+      // In case of Chess960, verify if the Rook blocks some checks
-      // not discover some hidden checker.
       // For instance an enemy queen in SQ_A1 when castling rook is in SQ_B1.
-      return   !chess960
+      return !chess960 || !(blockers_for_king(us) & to_sq(m));
-            || !(attacks_bb<ROOK>(to, pieces() ^ to_sq(m)) & pieces(~us, ROOK, QUEEN));
   }
 
   // If the moving piece is a king, check whether the destination square is
@@ -544,8 +546,8 @@ bool Position::legal(Move m) const {
 
   // A non-king move is legal if and only if it is not pinned or it
   // is moving along the ray towards or away from the king.
-  return   !(blockers_for_king(us) & from)
+  return !(blockers_for_king(us) & from)
-        ||  aligned(from, to, square<KING>(us));
+      || aligned(from, to, square<KING>(us));
 }
 
 
@@ -561,8 +563,10 @@ bool Position::pseudo_legal(const Move m) const {
   Piece pc = moved_piece(m);
 
   // Use a slower but simpler function for uncommon cases
+  // yet we skip the legality check of MoveList<LEGAL>().
   if (type_of(m) != NORMAL)
-      return MoveList<LEGAL>(*this).contains(m);
+      return checkers() ? MoveList<    EVASIONS>(*this).contains(m)
+                        : MoveList<NON_EVASIONS>(*this).contains(m);
 
   // Is not a promotion, so promotion piece must be empty
   if (promotion_type(m) - KNIGHT != NO_PIECE_TYPE)
@@ -648,31 +652,24 @@ bool Position::gives_check(Move m) const {
   case PROMOTION:
       return attacks_bb(promotion_type(m), to, pieces() ^ from) & square<KING>(~sideToMove);
 
-  // En passant capture with check? We have already handled the case
+  // The double-pushed pawn blocked a check? En Passant will remove the blocker.
-  // of direct checks and ordinary discovered check, so the only case we
+  // The only discovery check that wasn't handle is through capsq and fromsq
-  // need to handle is the unusual case of a discovered check through
+  // So the King must be in the same rank as fromsq to consider this possibility.
-  // the captured pawn.
+  // st->previous->blockersForKing consider capsq as empty.
-  case ENPASSANT:
+  case EN_PASSANT:
-  {
+      return st->previous->checkersBB
-      Square capsq = make_square(file_of(to), rank_of(from));
+          || (   rank_of(square<KING>(~sideToMove)) == rank_of(from)
-      Bitboard b = (pieces() ^ from ^ capsq) | to;
+              && st->previous->blockersForKing[~sideToMove] & from);
 
-      return  (attacks_bb<  ROOK>(square<KING>(~sideToMove), b) & pieces(sideToMove, QUEEN, ROOK))
+  default: //CASTLING
-            | (attacks_bb<BISHOP>(square<KING>(~sideToMove), b) & pieces(sideToMove, QUEEN, BISHOP));
-  }
-  case CASTLING:
   {
-      Square kfrom = from;
+      // Castling is encoded as 'king captures the rook'
-      Square rfrom = to; // Castling is encoded as 'king captures the rook'
+      Square ksq = square<KING>(~sideToMove);
-      Square kto = relative_square(sideToMove, rfrom > kfrom ? SQ_G1 : SQ_C1);
+      Square rto = relative_square(sideToMove, to > from ? SQ_F1 : SQ_D1);
-      Square rto = relative_square(sideToMove, rfrom > kfrom ? SQ_F1 : SQ_D1);
 
-      return   (attacks_bb<ROOK>(rto) & square<KING>(~sideToMove))
+      return   (attacks_bb<ROOK>(rto) & ksq)
-            && (attacks_bb<ROOK>(rto, (pieces() ^ kfrom ^ rfrom) | rto | kto) & square<KING>(~sideToMove));
+            && (attacks_bb<ROOK>(rto, pieces() ^ from ^ to) & ksq);
   }
-  default:
-      assert(false);
-      return false;
   }
 }
 
@@ -703,7 +700,8 @@ void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) {
   ++st->pliesFromNull;
 
   // Used by NNUE
-  st->accumulator.computed_accumulation = false;
+  st->accumulator.state[WHITE] = Eval::NNUE::EMPTY;
+  st->accumulator.state[BLACK] = Eval::NNUE::EMPTY;
   auto& dp = st->dirtyPiece;
   dp.dirty_num = 1;
 
@@ -712,7 +710,7 @@ void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) {
   Square from = from_sq(m);
   Square to = to_sq(m);
   Piece pc = piece_on(from);
-  Piece captured = type_of(m) == ENPASSANT ? make_piece(them, PAWN) : piece_on(to);
+  Piece captured = type_of(m) == EN_PASSANT ? make_piece(them, PAWN) : piece_on(to);
 
   assert(color_of(pc) == us);
   assert(captured == NO_PIECE || color_of(captured) == (type_of(m) != CASTLING ? them : us));
@@ -738,7 +736,7 @@ void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) {
       // update non-pawn material.
       if (type_of(captured) == PAWN)
       {
-          if (type_of(m) == ENPASSANT)
+          if (type_of(m) == EN_PASSANT)
           {
               capsq -= pawn_push(us);
 
@@ -765,7 +763,7 @@ void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) {
       // Update board and piece lists
       remove_piece(capsq);
 
-      if (type_of(m) == ENPASSANT)
+      if (type_of(m) == EN_PASSANT)
           board[capsq] = NO_PIECE;
 
       // Update material hash key and prefetch access to materialTable
@@ -811,7 +809,7 @@ void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) {
   // If the moving piece is a pawn do some special extra work
   if (type_of(pc) == PAWN)
   {
-      // Set en-passant square if the moved pawn can be captured
+      // Set en passant square if the moved pawn can be captured
       if (   (int(to) ^ int(from)) == 16
           && (pawn_attacks_bb(us, to - pawn_push(us)) & pieces(them, PAWN)))
       {
@@ -934,7 +932,7 @@ void Position::undo_move(Move m) {
       {
           Square capsq = to;
 
-          if (type_of(m) == ENPASSANT)
+          if (type_of(m) == EN_PASSANT)
           {
               capsq -= pawn_push(us);
 
@@ -996,16 +994,16 @@ void Position::do_null_move(StateInfo& newSt) {
   assert(!checkers());
   assert(&newSt != st);
 
-  if (Eval::useNNUE)
+  std::memcpy(&newSt, st, offsetof(StateInfo, accumulator));
-  {
-      std::memcpy(&newSt, st, sizeof(StateInfo));
-  }
-  else
-      std::memcpy(&newSt, st, offsetof(StateInfo, accumulator));
 
   newSt.previous = st;
   st = &newSt;
 
+  st->dirtyPiece.dirty_num = 0;
+  st->dirtyPiece.piece[0] = NO_PIECE; // Avoid checks in UpdateAccumulator()
+  st->accumulator.state[WHITE] = Eval::NNUE::EMPTY;
+  st->accumulator.state[BLACK] = Eval::NNUE::EMPTY;
+
   if (st->epSquare != SQ_NONE)
   {
       st->key ^= Zobrist::enpassant[file_of(st->epSquare)];
@@ -1013,7 +1011,7 @@ void Position::do_null_move(StateInfo& newSt) {
   }
 
   st->key ^= Zobrist::side;
-  prefetch(TT.first_entry(st->key));
+  prefetch(TT.first_entry(key()));
 
   ++st->rule50;
   st->pliesFromNull = 0;
@@ -1038,7 +1036,7 @@ void Position::undo_null_move() {
 
 /// Position::key_after() computes the new hash key after the given move. Needed
 /// for speculative prefetch. It doesn't recognize special moves like castling,
-/// en-passant and promotions.
+/// en passant and promotions.
 
 Key Position::key_after(Move m) const {
 
@@ -1063,7 +1061,7 @@ bool Position::see_ge(Move m, Value threshold) const {
 
   assert(is_ok(m));
 
-  // Only deal with normal moves, assume others pass a simple see
+  // Only deal with normal moves, assume others pass a simple SEE
   if (type_of(m) != NORMAL)
       return VALUE_ZERO >= threshold;
 
@@ -1315,21 +1313,17 @@ bool Position::pos_is_ok() const {
               assert(0 && "pos_is_ok: Bitboards");
 
   StateInfo si = *st;
+  ASSERT_ALIGNED(&si, Eval::NNUE::kCacheLineSize);
+
   set_state(&si);
   if (std::memcmp(&si, st, sizeof(StateInfo)))
       assert(0 && "pos_is_ok: State");
 
   for (Piece pc : Pieces)
-  {
       if (   pieceCount[pc] != popcount(pieces(color_of(pc), type_of(pc)))
           || pieceCount[pc] != std::count(board, board + SQUARE_NB, pc))
           assert(0 && "pos_is_ok: Pieces");
 
-      for (int i = 0; i < pieceCount[pc]; ++i)
-          if (board[pieceList[pc][i]] != pc || index[pieceList[pc][i]] != i)
-              assert(0 && "pos_is_ok: Index");
-  }
-
   for (Color c : { WHITE, BLACK })
       for (CastlingRights cr : {c & KING_SIDE, c & QUEEN_SIDE})
       {

DroidFishApp/src/main/cpp/stockfish/position.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -26,6 +26,7 @@
 
 #include "bitboard.h"
 #include "evaluate.h"
+#include "psqt.h"
 #include "types.h"
 
 #include "nnue/nnue_accumulator.h"
@@ -99,7 +100,6 @@ public:
   bool empty(Square s) const;
   template<PieceType Pt> int count(Color c) const;
   template<PieceType Pt> int count() const;
-  template<PieceType Pt> const Square* squares(Color c) const;
   template<PieceType Pt> Square square(Color c) const;
   bool is_on_semiopen_file(Color c, Square s) const;
 
@@ -114,7 +114,7 @@ public:
   Bitboard blockers_for_king(Color c) const;
   Bitboard check_squares(PieceType pt) const;
   Bitboard pinners(Color c) const;
-  bool is_discovery_check_on_king(Color c, Move m) const;
+  bool is_discovered_check_on_king(Color c, Move m) const;
 
   // Attacks to/from a given square
   Bitboard attackers_to(Square s) const;
@@ -190,8 +190,6 @@ private:
   Bitboard byTypeBB[PIECE_TYPE_NB];
   Bitboard byColorBB[COLOR_NB];
   int pieceCount[PIECE_NB];
-  Square pieceList[PIECE_NB][16];
-  int index[SQUARE_NB];
   int castlingRightsMask[SQUARE_NB];
   Square castlingRookSquare[CASTLING_RIGHT_NB];
   Bitboard castlingPath[CASTLING_RIGHT_NB];
@@ -203,10 +201,6 @@ private:
   bool chess960;
 };
 
-namespace PSQT {
-  extern Score psq[PIECE_NB][SQUARE_NB];
-}
-
 extern std::ostream& operator<<(std::ostream& os, const Position& pos);
 
 inline Color Position::side_to_move() const {
@@ -254,13 +248,9 @@ template<PieceType Pt> inline int Position::count() const {
   return count<Pt>(WHITE) + count<Pt>(BLACK);
 }
 
-template<PieceType Pt> inline const Square* Position::squares(Color c) const {
-  return pieceList[make_piece(c, Pt)];
-}
-
 template<PieceType Pt> inline Square Position::square(Color c) const {
-  assert(pieceCount[make_piece(c, Pt)] == 1);
+  assert(count<Pt>(c) == 1);
-  return squares<Pt>(c)[0];
+  return lsb(pieces(c, Pt));
 }
 
 inline Square Position::ep_square() const {
@@ -311,7 +301,7 @@ inline Bitboard Position::check_squares(PieceType pt) const {
   return st->checkSquares[pt];
 }
 
-inline bool Position::is_discovery_check_on_king(Color c, Move m) const {
+inline bool Position::is_discovered_check_on_king(Color c, Move m) const {
   return st->blockersForKing[c] & from_sq(m);
 }
 
@@ -329,7 +319,8 @@ inline int Position::pawns_on_same_color_squares(Color c, Square s) const {
 }
 
 inline Key Position::key() const {
-  return st->key;
+  return st->rule50 < 14 ? st->key
+                         : st->key ^ make_key((st->rule50 - 14) / 8);
 }
 
 inline Key Position::pawn_key() const {
@@ -378,7 +369,7 @@ inline bool Position::capture_or_promotion(Move m) const {
 inline bool Position::capture(Move m) const {
   assert(is_ok(m));
   // Castling is encoded as "king captures rook"
-  return (!empty(to_sq(m)) && type_of(m) != CASTLING) || type_of(m) == ENPASSANT;
+  return (!empty(to_sq(m)) && type_of(m) != CASTLING) || type_of(m) == EN_PASSANT;
 }
 
 inline Piece Position::captured_piece() const {
@@ -394,35 +385,25 @@ inline void Position::put_piece(Piece pc, Square s) {
   board[s] = pc;
   byTypeBB[ALL_PIECES] |= byTypeBB[type_of(pc)] |= s;
   byColorBB[color_of(pc)] |= s;
-  index[s] = pieceCount[pc]++;
+  pieceCount[pc]++;
-  pieceList[pc][index[s]] = s;
   pieceCount[make_piece(color_of(pc), ALL_PIECES)]++;
   psq += PSQT::psq[pc][s];
 }
 
 inline void Position::remove_piece(Square s) {
 
-  // WARNING: This is not a reversible operation. If we remove a piece in
-  // do_move() and then replace it in undo_move() we will put it at the end of
-  // the list and not in its original place, it means index[] and pieceList[]
-  // are not invariant to a do_move() + undo_move() sequence.
   Piece pc = board[s];
   byTypeBB[ALL_PIECES] ^= s;
   byTypeBB[type_of(pc)] ^= s;
   byColorBB[color_of(pc)] ^= s;
   /* board[s] = NO_PIECE;  Not needed, overwritten by the capturing one */
-  Square lastSquare = pieceList[pc][--pieceCount[pc]];
+  pieceCount[pc]--;
-  index[lastSquare] = index[s];
-  pieceList[pc][index[lastSquare]] = lastSquare;
-  pieceList[pc][pieceCount[pc]] = SQ_NONE;
   pieceCount[make_piece(color_of(pc), ALL_PIECES)]--;
   psq -= PSQT::psq[pc][s];
 }
 
 inline void Position::move_piece(Square from, Square to) {
 
-  // index[from] is not updated and becomes stale. This works as long as index[]
-  // is accessed just by known occupied squares.
   Piece pc = board[from];
   Bitboard fromTo = from | to;
   byTypeBB[ALL_PIECES] ^= fromTo;
@@ -430,8 +411,6 @@ inline void Position::move_piece(Square from, Square to) {
   byColorBB[color_of(pc)] ^= fromTo;
   board[from] = NO_PIECE;
   board[to] = pc;
-  index[to] = index[from];
-  pieceList[pc][index[to]] = to;
   psq += PSQT::psq[pc][to] - PSQT::psq[pc][from];
 }
 

DroidFishApp/src/main/cpp/stockfish/psqt.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -16,19 +16,22 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+
+#include "psqt.h"
+
 #include <algorithm>
 
-#include "types.h"
 #include "bitboard.h"
+#include "types.h"
 
-namespace PSQT {
 
-#define S(mg, eg) make_score(mg, eg)
+namespace
+{
 
-// Bonus[PieceType][Square / 2] contains Piece-Square scores. For each piece
+auto constexpr S = make_score;
-// type on a given square a (middlegame, endgame) score pair is assigned. Table
+
-// is defined for files A..D and white side: it is symmetric for black side and
+// 'Bonus' contains Piece-Square parameters.
-// second half of the files.
+// Scores are explicit for files A to D, implicitly mirrored for E to H.
 constexpr Score Bonus[][RANK_NB][int(FILE_NB) / 2] = {
   { },
   { },
@@ -43,14 +46,14 @@ constexpr Score Bonus[][RANK_NB][int(FILE_NB) / 2] = {
    { S(-201,-100), S(-83,-88), S(-56,-56), S(-26,-17) }
   },
   { // Bishop
-   { S(-53,-57), S( -5,-30), S( -8,-37), S(-23,-12) },
+   { S(-37,-40), S(-4 ,-21), S( -6,-26), S(-16, -8) },
-   { S(-15,-37), S(  8,-13), S( 19,-17), S(  4,  1) },
+   { S(-11,-26), S(  6, -9), S( 13,-12), S(  3,  1) },
-   { S( -7,-16), S( 21, -1), S( -5, -2), S( 17, 10) },
+   { S(-5 ,-11), S( 15, -1), S( -4, -1), S( 12,  7) },
-   { S( -5,-20), S( 11, -6), S( 25,  0), S( 39, 17) },
+   { S(-4 ,-14), S(  8, -4), S( 18,  0), S( 27, 12) },
-   { S(-12,-17), S( 29, -1), S( 22,-14), S( 31, 15) },
+   { S(-8 ,-12), S( 20, -1), S( 15,-10), S( 22, 11) },
-   { S(-16,-30), S(  6,  6), S(  1,  4), S( 11,  6) },
+   { S(-11,-21), S(  4,  4), S(  1,  3), S(  8,  4) },
-   { S(-17,-31), S(-14,-20), S(  5, -1), S(  0,  1) },
+   { S(-12,-22), S(-10,-14), S(  4, -1), S(  0,  1) },
-   { S(-48,-46), S(  1,-42), S(-14,-37), S(-23,-24) }
+   { S(-34,-32), S(  1,-29), S(-10,-26), S(-16,-17) }
   },
   { // Rook
    { S(-31, -9), S(-20,-13), S(-14,-10), S(-5, -9) },
@@ -64,13 +67,13 @@ constexpr Score Bonus[][RANK_NB][int(FILE_NB) / 2] = {
   },
   { // Queen
    { S( 3,-69), S(-5,-57), S(-5,-47), S( 4,-26) },
-   { S(-3,-55), S( 5,-31), S( 8,-22), S(12, -4) },
+   { S(-3,-54), S( 5,-31), S( 8,-22), S(12, -4) },
    { S(-3,-39), S( 6,-18), S(13, -9), S( 7,  3) },
    { S( 4,-23), S( 5, -3), S( 9, 13), S( 8, 24) },
    { S( 0,-29), S(14, -6), S(12,  9), S( 5, 21) },
-   { S(-4,-38), S(10,-18), S( 6,-12), S( 8,  1) },
+   { S(-4,-38), S(10,-18), S( 6,-11), S( 8,  1) },
    { S(-5,-50), S( 6,-27), S(10,-24), S( 8, -8) },
-   { S(-2,-75), S(-2,-52), S( 1,-43), S(-2,-36) }
+   { S(-2,-74), S(-2,-52), S( 1,-43), S(-2,-34) }
   },
   { // King
    { S(271,  1), S(327, 45), S(271, 85), S(198, 76) },
@@ -87,19 +90,22 @@ constexpr Score Bonus[][RANK_NB][int(FILE_NB) / 2] = {
 constexpr Score PBonus[RANK_NB][FILE_NB] =
   { // Pawn (asymmetric distribution)
    { },
-   { S(  3,-10), S(  3, -6), S( 10, 10), S( 19,  0), S( 16, 14), S( 19,  7), S(  7, -5), S( -5,-19) },
+   { S(  2, -8), S(  4, -6), S( 11,  9), S( 18,  5), S( 16, 16), S( 21,  6), S(  9, -6), S( -3,-18) },
-   { S( -9,-10), S(-15,-10), S( 11,-10), S( 15,  4), S( 32,  4), S( 22,  3), S(  5, -6), S(-22, -4) },
+   { S( -9, -9), S(-15, -7), S( 11,-10), S( 15,  5), S( 31,  2), S( 23,  3), S(  6, -8), S(-20, -5) },
-   { S( -4,  6), S(-23, -2), S(  6, -8), S( 20, -4), S( 40,-13), S( 17,-12), S(  4,-10), S( -8, -9) },
+   { S( -3,  7), S(-20,  1), S(  8, -8), S( 19, -2), S( 39,-14), S( 17,-13), S(  2,-11), S( -5, -6) },
-   { S( 13, 10), S(  0,  5), S(-13,  4), S(  1, -5), S( 11, -5), S( -2, -5), S(-13, 14), S(  5,  9) },
+   { S( 11, 12), S( -4,  6), S(-11,  2), S(  2, -6), S( 11, -5), S(  0, -4), S(-12, 14), S(  5,  9) },
-   { S(  5, 28), S(-12, 20), S( -7, 21), S( 22, 28), S( -8, 30), S( -5,  7), S(-15,  6), S( -8, 13) },
+   { S(  3, 27), S(-11, 18), S( -6, 19), S( 22, 29), S( -8, 30), S( -5,  9), S(-14,  8), S(-11, 14) },
-   { S( -7,  0), S(  7,-11), S( -3, 12), S(-13, 21), S(  5, 25), S(-16, 19), S( 10,  4), S( -8,  7) }
+   { S( -7, -1), S(  6,-14), S( -2, 13), S(-11, 22), S(  4, 24), S(-14, 17), S( 10,  7), S( -9,  7) }
   };
 
-#undef S
+} // namespace
+
+
+namespace PSQT
+{
 
 Score psq[PIECE_NB][SQUARE_NB];
 
-
 // PSQT::init() initializes piece-square tables: the white halves of the tables are
 // copied from Bonus[] and PBonus[], adding the piece value, then the black halves of
 // the tables are initialized by flipping and changing the sign of the white scores.
@@ -107,15 +113,15 @@ void init() {
 
   for (Piece pc : {W_PAWN, W_KNIGHT, W_BISHOP, W_ROOK, W_QUEEN, W_KING})
   {
-      Score score = make_score(PieceValue[MG][pc], PieceValue[EG][pc]);
+    Score score = make_score(PieceValue[MG][pc], PieceValue[EG][pc]);
 
-      for (Square s = SQ_A1; s <= SQ_H8; ++s)
+    for (Square s = SQ_A1; s <= SQ_H8; ++s)
-      {
+    {
-          File f = File(edge_distance(file_of(s)));
+      File f = File(edge_distance(file_of(s)));
-          psq[ pc][s] = score + (type_of(pc) == PAWN ? PBonus[rank_of(s)][file_of(s)]
+      psq[ pc][s] = score + (type_of(pc) == PAWN ? PBonus[rank_of(s)][file_of(s)]
-                                                     : Bonus[pc][rank_of(s)][f]);
+                                                 : Bonus[pc][rank_of(s)][f]);
-          psq[~pc][flip_rank(s)] = -psq[pc][s];
+      psq[~pc][flip_rank(s)] = -psq[pc][s];
-      }
+    }
   }
 }
 

DroidFishApp/src/main/cpp/stockfish/psqt.h

@@ -0,0 +1,38 @@
+/*
+  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
+  Copyright (C) 2004-2021 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/>.
+*/
+
+
+#ifndef PSQT_H_INCLUDED
+#define PSQT_H_INCLUDED
+
+
+#include "types.h"
+
+
+namespace PSQT
+{
+
+extern Score psq[PIECE_NB][SQUARE_NB];
+
+// Fill psqt array from a set of internally linked parameters
+extern void init();
+
+} // namespace PSQT
+
+
+#endif // PSQT_H_INCLUDED

DroidFishApp/src/main/cpp/stockfish/search.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -62,10 +62,9 @@ namespace {
   constexpr uint64_t TtHitAverageWindow     = 4096;
   constexpr uint64_t TtHitAverageResolution = 1024;
 
-  // Razor and futility margins
+  // Futility margin
-  constexpr int RazorMargin = 510;
   Value futility_margin(Depth d, bool improving) {
-    return Value(223 * (d - improving));
+    return Value(234 * (d - improving));
   }
 
   // Reductions lookup table, initialized at startup
@@ -73,7 +72,7 @@ namespace {
 
   Depth reduction(bool i, Depth d, int mn) {
     int r = Reductions[d] * Reductions[mn];
-    return (r + 509) / 1024 + (!i && r > 894);
+    return (r + 503) / 1024 + (!i && r > 915);
   }
 
   constexpr int futility_move_count(bool improving, Depth depth) {
@@ -82,10 +81,10 @@ namespace {
 
   // History and stats update bonus, based on depth
   int stat_bonus(Depth d) {
-    return d > 13 ? 29 : 17 * d * d + 134 * d - 134;
+    return d > 14 ? 66 : 6 * d * d + 231 * d - 206;
   }
 
-  // Add a small random component to draw evaluations to avoid 3fold-blindness
+  // Add a small random component to draw evaluations to avoid 3-fold blindness
   Value value_draw(Thread* thisThread) {
     return VALUE_DRAW + Value(2 * (thisThread->nodes & 1) - 1);
   }
@@ -164,6 +163,8 @@ namespace {
   uint64_t perft(Position& pos, Depth depth) {
 
     StateInfo st;
+    ASSERT_ALIGNED(&st, Eval::NNUE::kCacheLineSize);
+
     uint64_t cnt, nodes = 0;
     const bool leaf = (depth == 2);
 
@@ -192,7 +193,7 @@ namespace {
 void Search::init() {
 
   for (int i = 1; i < MAX_MOVES; ++i)
-      Reductions[i] = int((22.0 + 2 * std::log(Threads.size())) * std::log(i + 0.25 * std::log(i)));
+      Reductions[i] = int((21.3 + 2 * std::log(Threads.size())) * std::log(i + 0.25 * std::log(i)));
 }
 
 
@@ -408,7 +409,7 @@ void Thread::search() {
               beta  = std::min(prev + delta, VALUE_INFINITE);
 
               // Adjust contempt based on root move's previousScore (dynamic contempt)
-              int dct = ct + (105 - ct / 2) * prev / (abs(prev) + 149);
+              int dct = ct + (113 - ct / 2) * prev / (abs(prev) + 147);
 
               contempt = (us == WHITE ?  make_score(dct, dct / 2)
                                       : -make_score(dct, dct / 2));
@@ -417,7 +418,7 @@ void Thread::search() {
           // Start with a small aspiration window and, in the case of a fail
           // high/low, re-search with a bigger window until we don't fail
           // high/low anymore.
-          int failedHighCnt = 0;
+          failedHighCnt = 0;
           while (true)
           {
               Depth adjustedDepth = std::max(1, rootDepth - failedHighCnt - searchAgainCounter);
@@ -519,10 +520,14 @@ void Thread::search() {
           }
           double bestMoveInstability = 1 + 2 * totBestMoveChanges / Threads.size();
 
-          double totalTime = rootMoves.size() == 1 ? 0 :
+          double totalTime = Time.optimum() * fallingEval * reduction * bestMoveInstability;
-                             Time.optimum() * fallingEval * reduction * bestMoveInstability;
 
-          // Stop the search if we have exceeded the totalTime, at least 1ms search
+          // Cap used time in case of a single legal move for a better viewer experience in tournaments
+          // yielding correct scores and sufficiently fast moves.
+          if (rootMoves.size() == 1)
+              totalTime = std::min(500.0, totalTime);
+
+          // Stop the search if we have exceeded the totalTime
           if (Time.elapsed() > totalTime)
           {
               // If we are allowed to ponder do not stop the search now but
@@ -565,6 +570,7 @@ namespace {
 
     constexpr bool PvNode = NT == PV;
     const bool rootNode = PvNode && ss->ply == 0;
+    const Depth maxNextDepth = rootNode ? depth : depth + 1;
 
     // Check if we have an upcoming move which draws by repetition, or
     // if the opponent had an alternative move earlier to this position.
@@ -589,6 +595,8 @@ namespace {
 
     Move pv[MAX_PLY+1], capturesSearched[32], quietsSearched[64];
     StateInfo st;
+    ASSERT_ALIGNED(&st, Eval::NNUE::kCacheLineSize);
+
     TTEntry* tte;
     Key posKey;
     Move ttMove, move, excludedMove, bestMove;
@@ -667,6 +675,7 @@ namespace {
         ss->ttPv = PvNode || (ss->ttHit && tte->is_pv());
     formerPv = ss->ttPv && !PvNode;
 
+    // Update low ply history for previous move if we are near root and position is or has been in PV
     if (   ss->ttPv
         && depth > 12
         && ss->ply - 1 < MAX_LPH
@@ -691,6 +700,7 @@ namespace {
         {
             if (ttValue >= beta)
             {
+                // Bonus for a quiet ttMove that fails high
                 if (!pos.capture_or_promotion(ttMove))
                     update_quiet_stats(pos, ss, ttMove, stat_bonus(depth), depth);
 
@@ -707,6 +717,8 @@ namespace {
             }
         }
 
+        // Partial workaround for the graph history interaction problem
+        // For high rule50 counts don't produce transposition table cutoffs.
         if (pos.rule50_count() < 90)
             return ttValue;
     }
@@ -780,6 +792,7 @@ namespace {
         if (eval == VALUE_NONE)
             ss->staticEval = eval = evaluate(pos);
 
+        // Randomize draw evaluation
         if (eval == VALUE_DRAW)
             eval = value_draw(thisThread);
 
@@ -790,38 +803,46 @@ namespace {
     }
     else
     {
+        // In case of null move search use previous static eval with a different sign
+        // and addition of two tempos
         if ((ss-1)->currentMove != MOVE_NULL)
             ss->staticEval = eval = evaluate(pos);
         else
             ss->staticEval = eval = -(ss-1)->staticEval + 2 * Tempo;
 
+        // Save static evaluation into transposition table
         tte->save(posKey, VALUE_NONE, ss->ttPv, BOUND_NONE, DEPTH_NONE, MOVE_NONE, eval);
     }
 
-    // Step 7. Razoring (~1 Elo)
+    // Use static evaluation difference to improve quiet move ordering
-    if (   !rootNode // The required rootNode PV handling is not available in qsearch
+    if (is_ok((ss-1)->currentMove) && !(ss-1)->inCheck && !priorCapture)
-        &&  depth == 1
+    {
-        &&  eval <= alpha - RazorMargin)
+        int bonus = std::clamp(-depth * 4 * int((ss-1)->staticEval + ss->staticEval - 2 * Tempo), -1000, 1000);
-        return qsearch<NT>(pos, ss, alpha, beta);
+        thisThread->mainHistory[~us][from_to((ss-1)->currentMove)] << bonus;
+    }
 
+    // Set up improving flag that is used in various pruning heuristics
+    // We define position as improving if static evaluation of position is better
+    // Than the previous static evaluation at our turn
+    // In case of us being in check at our previous move we look at move prior to it
     improving =  (ss-2)->staticEval == VALUE_NONE
                ? ss->staticEval > (ss-4)->staticEval || (ss-4)->staticEval == VALUE_NONE
                : ss->staticEval > (ss-2)->staticEval;
 
-    // Step 8. Futility pruning: child node (~50 Elo)
+    // Step 7. Futility pruning: child node (~50 Elo)
     if (   !PvNode
-        &&  depth < 8
+        &&  depth < 9
         &&  eval - futility_margin(depth, improving) >= beta
         &&  eval < VALUE_KNOWN_WIN) // Do not return unproven wins
         return eval;
 
-    // Step 9. Null move search with verification search (~40 Elo)
+    // Step 8. Null move search with verification search (~40 Elo)
     if (   !PvNode
         && (ss-1)->currentMove != MOVE_NULL
-        && (ss-1)->statScore < 22977
+        && (ss-1)->statScore < 22661
         &&  eval >= beta
         &&  eval >= ss->staticEval
-        &&  ss->staticEval >= beta - 30 * depth - 28 * improving + 84 * ss->ttPv + 182
+        &&  ss->staticEval >= beta - 24 * depth - 34 * improving + 162 * ss->ttPv + 159
         && !excludedMove
         &&  pos.non_pawn_material(us)
         && (ss->ply >= thisThread->nmpMinPly || us != thisThread->nmpColor))
@@ -829,7 +850,7 @@ namespace {
         assert(eval - beta >= 0);
 
         // Null move dynamic reduction based on depth and value
-        Depth R = (982 + 85 * depth) / 256 + std::min(int(eval - beta) / 192, 3);
+        Depth R = (1062 + 68 * depth) / 256 + std::min(int(eval - beta) / 190, 3);
 
         ss->currentMove = MOVE_NULL;
         ss->continuationHistory = &thisThread->continuationHistory[0][0][NO_PIECE][0];
@@ -846,7 +867,7 @@ namespace {
             if (nullValue >= VALUE_TB_WIN_IN_MAX_PLY)
                 nullValue = beta;
 
-            if (thisThread->nmpMinPly || (abs(beta) < VALUE_KNOWN_WIN && depth < 13))
+            if (thisThread->nmpMinPly || (abs(beta) < VALUE_KNOWN_WIN && depth < 14))
                 return nullValue;
 
             assert(!thisThread->nmpMinPly); // Recursive verification is not allowed
@@ -865,9 +886,9 @@ namespace {
         }
     }
 
-    probCutBeta = beta + 176 - 49 * improving;
+    probCutBeta = beta + 209 - 44 * improving;
 
-    // Step 10. ProbCut (~10 Elo)
+    // Step 9. ProbCut (~10 Elo)
     // If we have a good enough capture and a reduced search returns a value
     // much above beta, we can (almost) safely prune the previous move.
     if (   !PvNode
@@ -940,7 +961,7 @@ namespace {
          ss->ttPv = ttPv;
     }
 
-    // Step 11. If the position is not in TT, decrease depth by 2
+    // Step 10. If the position is not in TT, decrease depth by 2
     if (   PvNode
         && depth >= 6
         && !ttMove)
@@ -969,7 +990,7 @@ moves_loop: // When in check, search starts from here
     // Mark this node as being searched
     ThreadHolding th(thisThread, posKey, ss->ply);
 
-    // Step 12. Loop through all pseudo-legal moves until no moves remain
+    // Step 11. Loop through all pseudo-legal moves until no moves remain
     // or a beta cutoff occurs.
     while ((move = mp.next_move(moveCountPruning)) != MOVE_NONE)
     {
@@ -1004,10 +1025,18 @@ moves_loop: // When in check, search starts from here
       movedPiece = pos.moved_piece(move);
       givesCheck = pos.gives_check(move);
 
+      // Indicate PvNodes that will probably fail low if node was searched with non-PV search
+      // at depth equal or greater to current depth and result of this search was far below alpha
+      bool likelyFailLow =    PvNode
+                           && ttMove
+                           && (tte->bound() & BOUND_UPPER)
+                           && ttValue < alpha + 200 + 100 * depth
+                           && tte->depth() >= depth;
+
       // Calculate new depth for this move
       newDepth = depth - 1;
 
-      // Step 13. Pruning at shallow depth (~200 Elo)
+      // Step 12. Pruning at shallow depth (~200 Elo)
       if (  !rootNode
           && pos.non_pawn_material(us)
           && bestValue > VALUE_TB_LOSS_IN_MAX_PLY)
@@ -1018,8 +1047,20 @@ moves_loop: // When in check, search starts from here
           // Reduced depth of the next LMR search
           int lmrDepth = std::max(newDepth - reduction(improving, depth, moveCount), 0);
 
-          if (   !captureOrPromotion
+          if (   captureOrPromotion
-              && !givesCheck)
+              || givesCheck)
+          {
+              // Capture history based pruning when the move doesn't give check
+              if (   !givesCheck
+                  && lmrDepth < 1
+                  && captureHistory[movedPiece][to_sq(move)][type_of(pos.piece_on(to_sq(move)))] < 0)
+                  continue;
+
+              // SEE based pruning
+              if (!pos.see_ge(move, Value(-218) * depth)) // (~25 Elo)
+                  continue;
+          }
+          else
           {
               // Countermoves based pruning (~20 Elo)
               if (   lmrDepth < 4 + ((ss-1)->statScore > 0 || (ss-1)->moveCount == 1)
@@ -1030,41 +1071,20 @@ moves_loop: // When in check, search starts from here
               // Futility pruning: parent node (~5 Elo)
               if (   lmrDepth < 7
                   && !ss->inCheck
-                  && ss->staticEval + 283 + 170 * lmrDepth <= alpha
+                  && ss->staticEval + 174 + 157 * lmrDepth <= alpha
                   &&  (*contHist[0])[movedPiece][to_sq(move)]
                     + (*contHist[1])[movedPiece][to_sq(move)]
                     + (*contHist[3])[movedPiece][to_sq(move)]
-                    + (*contHist[5])[movedPiece][to_sq(move)] / 2 < 27376)
+                    + (*contHist[5])[movedPiece][to_sq(move)] / 3 < 26237)
                   continue;
 
               // Prune moves with negative SEE (~20 Elo)
-              if (!pos.see_ge(move, Value(-(29 - std::min(lmrDepth, 18)) * lmrDepth * lmrDepth)))
+              if (!pos.see_ge(move, Value(-(30 - std::min(lmrDepth, 18)) * lmrDepth * lmrDepth)))
-                  continue;
-          }
-          else
-          {
-              // Capture history based pruning when the move doesn't give check
-              if (   !givesCheck
-                  && lmrDepth < 1
-                  && captureHistory[movedPiece][to_sq(move)][type_of(pos.piece_on(to_sq(move)))] < 0)
-                  continue;
-
-              // Futility pruning for captures
-              if (   !givesCheck
-                  && lmrDepth < 6
-                  && !(PvNode && abs(bestValue) < 2)
-                  && !ss->inCheck
-                  && ss->staticEval + 169 + 244 * lmrDepth
-                     + PieceValue[MG][type_of(pos.piece_on(to_sq(move)))] <= alpha)
-                  continue;
-
-              // See based pruning
-              if (!pos.see_ge(move, Value(-221) * depth)) // (~25 Elo)
                   continue;
           }
       }
 
-      // Step 14. Extensions (~75 Elo)
+      // Step 13. Extensions (~75 Elo)
 
       // Singular extension search (~70 Elo). If all moves but one fail low on a
       // search of (alpha-s, beta-s), and just one fails high on (alpha, beta),
@@ -1115,7 +1135,7 @@ moves_loop: // When in check, search starts from here
 
       // Check extension (~2 Elo)
       else if (    givesCheck
-               && (pos.is_discovery_check_on_king(~us, move) || pos.see_ge(move)))
+               && (pos.is_discovered_check_on_king(~us, move) || pos.see_ge(move)))
           extension = 1;
 
       // Last captures extension
@@ -1123,12 +1143,6 @@ moves_loop: // When in check, search starts from here
                && pos.non_pawn_material() <= 2 * RookValueMg)
           extension = 1;
 
-      // Late irreversible move extension
-      if (   move == ttMove
-          && pos.rule50_count() > 80
-          && (captureOrPromotion || type_of(movedPiece) == PAWN))
-          extension = 2;
-
       // Add extension to new depth
       newDepth += extension;
 
@@ -1142,10 +1156,10 @@ moves_loop: // When in check, search starts from here
                                                                 [movedPiece]
                                                                 [to_sq(move)];
 
-      // Step 15. Make the move
+      // Step 14. Make the move
       pos.do_move(move, st, givesCheck);
 
-      // Step 16. Reduced depth search (LMR, ~200 Elo). If the move fails high it will be
+      // Step 15. Reduced depth search (LMR, ~200 Elo). If the move fails high it will be
       // re-searched at full depth.
       if (    depth >= 3
           &&  moveCount > 1 + 2 * rootNode
@@ -1153,22 +1167,29 @@ moves_loop: // When in check, search starts from here
               || moveCountPruning
               || ss->staticEval + PieceValue[EG][pos.captured_piece()] <= alpha
               || cutNode
-              || thisThread->ttHitAverage < 427 * TtHitAverageResolution * TtHitAverageWindow / 1024))
+              || (!PvNode && !formerPv && captureHistory[movedPiece][to_sq(move)][type_of(pos.captured_piece())] < 4506)
+              || thisThread->ttHitAverage < 432 * TtHitAverageResolution * TtHitAverageWindow / 1024))
       {
           Depth r = reduction(improving, depth, moveCount);
 
           // Decrease reduction if the ttHit running average is large
-          if (thisThread->ttHitAverage > 509 * TtHitAverageResolution * TtHitAverageWindow / 1024)
+          if (thisThread->ttHitAverage > 537 * TtHitAverageResolution * TtHitAverageWindow / 1024)
               r--;
 
-          // Reduction if other threads are searching this position
+          // Increase reduction if other threads are searching this position
           if (th.marked())
               r++;
 
-          // Decrease reduction if position is or has been on the PV (~10 Elo)
+          // Decrease reduction if position is or has been on the PV
-          if (ss->ttPv)
+          // and node is not likely to fail low. (~10 Elo)
+          if (ss->ttPv && !likelyFailLow)
               r -= 2;
 
+          // Increase reduction at root and non-PV nodes when the best move does not change frequently
+          if ((rootNode || !PvNode) && thisThread->rootDepth > 10 && thisThread->bestMoveChanges <= 2)
+              r++;
+
+          // More reductions for late moves if position was not in previous PV
           if (moveCountPruning && !formerPv)
               r++;
 
@@ -1180,12 +1201,22 @@ moves_loop: // When in check, search starts from here
           if (singularQuietLMR)
               r--;
 
-          if (!captureOrPromotion)
+          if (captureOrPromotion)
+          {
+              // Unless giving check, this capture is likely bad
+              if (   !givesCheck
+                  && ss->staticEval + PieceValue[EG][pos.captured_piece()] + 210 * depth <= alpha)
+                  r++;
+          }
+          else
           {
               // Increase reduction if ttMove is a capture (~5 Elo)
               if (ttCapture)
                   r++;
 
+              // Increase reduction at root if failing high
+              r += rootNode ? thisThread->failedHighCnt * thisThread->failedHighCnt * moveCount / 512 : 0;
+
               // Increase reduction for cut nodes (~10 Elo)
               if (cutNode)
                   r += 2;
@@ -1201,28 +1232,23 @@ moves_loop: // When in check, search starts from here
                              + (*contHist[0])[movedPiece][to_sq(move)]
                              + (*contHist[1])[movedPiece][to_sq(move)]
                              + (*contHist[3])[movedPiece][to_sq(move)]
-                             - 5287;
+                             - 5337;
 
               // Decrease/increase reduction by comparing opponent's stat score (~10 Elo)
-              if (ss->statScore >= -106 && (ss-1)->statScore < -104)
+              if (ss->statScore >= -89 && (ss-1)->statScore < -116)
                   r--;
 
-              else if ((ss-1)->statScore >= -119 && ss->statScore < -140)
+              else if ((ss-1)->statScore >= -112 && ss->statScore < -100)
                   r++;
 
               // Decrease/increase reduction for moves with a good/bad history (~30 Elo)
-              r -= ss->statScore / 14884;
+              // If we are not in check use statScore, if we are in check
-          }
+              // use sum of main history and first continuation history with an offset
-          else
+              if (ss->inCheck)
-          {
+                  r -= (thisThread->mainHistory[us][from_to(move)]
-              // Increase reduction for captures/promotions if late move and at low depth
+                     + (*contHist[0])[movedPiece][to_sq(move)] - 4341) / 16384;
-              if (depth < 8 && moveCount > 2)
+              else
-                  r++;
+                  r -= ss->statScore / 14382;
-
-              // Unless giving check, this capture is likely bad
-              if (   !givesCheck
-                  && ss->staticEval + PieceValue[EG][pos.captured_piece()] + 213 * depth <= alpha)
-                  r++;
           }
 
           Depth d = std::clamp(newDepth - r, 1, newDepth);
@@ -1240,19 +1266,17 @@ moves_loop: // When in check, search starts from here
           didLMR = false;
       }
 
-      // Step 17. Full depth search when LMR is skipped or fails high
+      // Step 16. Full depth search when LMR is skipped or fails high
       if (doFullDepthSearch)
       {
           value = -search<NonPV>(pos, ss+1, -(alpha+1), -alpha, newDepth, !cutNode);
 
+          // If the move passed LMR update its stats
           if (didLMR && !captureOrPromotion)
           {
               int bonus = value > alpha ?  stat_bonus(newDepth)
                                         : -stat_bonus(newDepth);
 
-              if (move == ss->killers[0])
-                  bonus += bonus / 4;
-
               update_continuation_histories(ss, movedPiece, to_sq(move), bonus);
           }
       }
@@ -1265,15 +1289,16 @@ moves_loop: // When in check, search starts from here
           (ss+1)->pv = pv;
           (ss+1)->pv[0] = MOVE_NONE;
 
-          value = -search<PV>(pos, ss+1, -beta, -alpha, newDepth, false);
+          value = -search<PV>(pos, ss+1, -beta, -alpha,
+                              std::min(maxNextDepth, newDepth), false);
       }
 
-      // Step 18. Undo move
+      // Step 17. Undo move
       pos.undo_move(move);
 
       assert(value > -VALUE_INFINITE && value < VALUE_INFINITE);
 
-      // Step 19. Check for a new best move
+      // Step 18. Check for a new best move
       // Finished searching the move. If a stop occurred, the return value of
       // the search cannot be trusted, and we return immediately without
       // updating best move, PV and TT.
@@ -1298,8 +1323,7 @@ moves_loop: // When in check, search starts from here
                   rm.pv.push_back(*m);
 
               // We record how often the best move has been changed in each
-              // iteration. This information is used for time management: when
+              // iteration. This information is used for time management and LMR
-              // the best move changes frequently, we allocate some more time.
               if (moveCount > 1)
                   ++thisThread->bestMoveChanges;
           }
@@ -1332,6 +1356,7 @@ moves_loop: // When in check, search starts from here
           }
       }
 
+      // If the move is worse than some previously searched move, remember it to update its stats later
       if (move != bestMove)
       {
           if (captureOrPromotion && captureCount < 32)
@@ -1350,7 +1375,7 @@ moves_loop: // When in check, search starts from here
         return VALUE_DRAW;
     */
 
-    // Step 20. Check for mate and stalemate
+    // Step 19. Check for mate and stalemate
     // All legal moves have been searched and if there are no legal moves, it
     // must be a mate or a stalemate. If we are in a singular extension search then
     // return a fail low score.
@@ -1361,6 +1386,7 @@ moves_loop: // When in check, search starts from here
         bestValue = excludedMove ? alpha
                    :     ss->inCheck ? mated_in(ss->ply) : VALUE_DRAW;
 
+    // If there is a move which produces search value greater than alpha we update stats of searched moves
     else if (bestMove)
         update_all_stats(pos, ss, bestMove, bestValue, beta, prevSq,
                          quietsSearched, quietCount, capturesSearched, captureCount, depth);
@@ -1382,6 +1408,7 @@ moves_loop: // When in check, search starts from here
     else if (depth > 3)
         ss->ttPv = ss->ttPv && (ss+1)->ttPv;
 
+    // Write gathered information in transposition table
     if (!excludedMove && !(rootNode && thisThread->pvIdx))
         tte->save(posKey, value_to_tt(bestValue, ss->ply), ss->ttPv,
                   bestValue >= beta ? BOUND_LOWER :
@@ -1407,6 +1434,8 @@ moves_loop: // When in check, search starts from here
 
     Move pv[MAX_PLY+1];
     StateInfo st;
+    ASSERT_ALIGNED(&st, Eval::NNUE::kCacheLineSize);
+
     TTEntry* tte;
     Key posKey;
     Move ttMove, move, bestMove;
@@ -1475,6 +1504,8 @@ moves_loop: // When in check, search starts from here
                 bestValue = ttValue;
         }
         else
+            // In case of null move search use previous static eval with a different sign
+            // and addition of two tempos
             ss->staticEval = bestValue =
             (ss-1)->currentMove != MOVE_NULL ? evaluate(pos)
                                              : -(ss-1)->staticEval + 2 * Tempo;
@@ -1482,6 +1513,7 @@ moves_loop: // When in check, search starts from here
         // Stand pat. Return immediately if static value is at least beta
         if (bestValue >= beta)
         {
+            // Save gathered info in transposition table
             if (!ss->ttHit)
                 tte->save(posKey, value_to_tt(bestValue, ss->ply), false, BOUND_LOWER,
                           DEPTH_NONE, MOVE_NONE, ss->staticEval);
@@ -1492,7 +1524,7 @@ moves_loop: // When in check, search starts from here
         if (PvNode && bestValue > alpha)
             alpha = bestValue;
 
-        futilityBase = bestValue + 145;
+        futilityBase = bestValue + 155;
     }
 
     const PieceToHistory* contHist[] = { (ss-1)->continuationHistory, (ss-2)->continuationHistory,
@@ -1519,12 +1551,12 @@ moves_loop: // When in check, search starts from here
       moveCount++;
 
       // Futility pruning
-      if (   !ss->inCheck
+      if (    bestValue > VALUE_TB_LOSS_IN_MAX_PLY
           && !givesCheck
           &&  futilityBase > -VALUE_KNOWN_WIN
           && !pos.advanced_pawn_push(move))
       {
-          assert(type_of(move) != ENPASSANT); // Due to !pos.advanced_pawn_push
+          assert(type_of(move) != EN_PASSANT); // Due to !pos.advanced_pawn_push
 
           // moveCount pruning
           if (moveCount > 2)
@@ -1546,8 +1578,7 @@ moves_loop: // When in check, search starts from here
       }
 
       // Do not search moves with negative SEE values
-      if (   !ss->inCheck
+      if (    bestValue > VALUE_TB_LOSS_IN_MAX_PLY
-          && !(givesCheck && pos.is_discovery_check_on_king(~pos.side_to_move(), move))
           && !pos.see_ge(move))
           continue;
 
@@ -1569,7 +1600,7 @@ moves_loop: // When in check, search starts from here
 
       // CounterMove based pruning
       if (  !captureOrPromotion
-          && moveCount
+          && bestValue > VALUE_TB_LOSS_IN_MAX_PLY
           && (*contHist[0])[pos.moved_piece(move)][to_sq(move)] < CounterMovePruneThreshold
           && (*contHist[1])[pos.moved_piece(move)][to_sq(move)] < CounterMovePruneThreshold)
           continue;
@@ -1604,8 +1635,13 @@ moves_loop: // When in check, search starts from here
     // All legal moves have been searched. A special case: if we're in check
     // and no legal moves were found, it is checkmate.
     if (ss->inCheck && bestValue == -VALUE_INFINITE)
-        return mated_in(ss->ply); // Plies to mate from the root
+    {
+        assert(!MoveList<LEGAL>(pos).size());
 
+        return mated_in(ss->ply); // Plies to mate from the root
+    }
+
+    // Save gathered info in transposition table
     tte->save(posKey, value_to_tt(bestValue, ss->ply), pvHit,
               bestValue >= beta ? BOUND_LOWER :
               PvNode && bestValue > oldAlpha  ? BOUND_EXACT : BOUND_UPPER,
@@ -1684,14 +1720,15 @@ moves_loop: // When in check, search starts from here
     PieceType captured = type_of(pos.piece_on(to_sq(bestMove)));
 
     bonus1 = stat_bonus(depth + 1);
-    bonus2 = bestValue > beta + PawnValueMg ? bonus1               // larger bonus
+    bonus2 = bestValue > beta + PawnValueMg ? bonus1                                 // larger bonus
-                                            : stat_bonus(depth);   // smaller bonus
+                                            : std::min(bonus1, stat_bonus(depth));   // smaller bonus
 
     if (!pos.capture_or_promotion(bestMove))
     {
+        // Increase stats for the best move in case it was a quiet move
         update_quiet_stats(pos, ss, bestMove, bonus2, depth);
 
-        // Decrease all the non-best quiet moves
+        // Decrease stats for all non-best quiet moves
         for (int i = 0; i < quietCount; ++i)
         {
             thisThread->mainHistory[us][from_to(quietsSearched[i])] << -bonus2;
@@ -1699,14 +1736,16 @@ moves_loop: // When in check, search starts from here
         }
     }
     else
+        // Increase stats for the best move in case it was a capture move
         captureHistory[moved_piece][to_sq(bestMove)][captured] << bonus1;
 
-    // Extra penalty for a quiet early move that was not a TT move or main killer move in previous ply when it gets refuted
+    // Extra penalty for a quiet early move that was not a TT move or
+    // main killer move in previous ply when it gets refuted.
     if (   ((ss-1)->moveCount == 1 + (ss-1)->ttHit || ((ss-1)->currentMove == (ss-1)->killers[0]))
         && !pos.captured_piece())
             update_continuation_histories(ss-1, pos.piece_on(prevSq), prevSq, -bonus1);
 
-    // Decrease all the non-best capture moves
+    // Decrease stats for all non-best capture moves
     for (int i = 0; i < captureCount; ++i)
     {
         moved_piece = pos.moved_piece(capturesSearched[i]);
@@ -1723,6 +1762,7 @@ moves_loop: // When in check, search starts from here
 
     for (int i : {1, 2, 4, 6})
     {
+        // Only update first 2 continuation histories if we are in check
         if (ss->inCheck && i > 2)
             break;
         if (is_ok((ss-i)->currentMove))
@@ -1735,6 +1775,7 @@ moves_loop: // When in check, search starts from here
 
   void update_quiet_stats(const Position& pos, Stack* ss, Move move, int bonus, int depth) {
 
+    // Update killers
     if (ss->killers[0] != move)
     {
         ss->killers[1] = ss->killers[0];
@@ -1746,15 +1787,18 @@ moves_loop: // When in check, search starts from here
     thisThread->mainHistory[us][from_to(move)] << bonus;
     update_continuation_histories(ss, pos.moved_piece(move), to_sq(move), bonus);
 
+    // Penalty for reversed move in case of moved piece not being a pawn
     if (type_of(pos.moved_piece(move)) != PAWN)
         thisThread->mainHistory[us][from_to(reverse_move(move))] << -bonus;
 
+    // Update countermove history
     if (is_ok((ss-1)->currentMove))
     {
         Square prevSq = to_sq((ss-1)->currentMove);
         thisThread->counterMoves[pos.piece_on(prevSq)][prevSq] = move;
     }
 
+    // Update low ply history
     if (depth > 11 && ss->ply < MAX_LPH)
         thisThread->lowPlyHistory[ss->ply][from_to(move)] << stat_bonus(depth - 7);
   }
@@ -1898,6 +1942,8 @@ string UCI::pv(const Position& pos, Depth depth, Value alpha, Value beta) {
 bool RootMove::extract_ponder_from_tt(Position& pos) {
 
     StateInfo st;
+    ASSERT_ALIGNED(&st, Eval::NNUE::kCacheLineSize);
+
     bool ttHit;
 
     assert(pv.size() == 1);

DroidFishApp/src/main/cpp/stockfish/search.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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

DroidFishApp/src/main/cpp/stockfish/syzygy/tbprobe.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -472,8 +472,6 @@ TBTables TBTables;
 // If the corresponding file exists two new objects TBTable<WDL> and TBTable<DTZ>
 // are created and added to the lists and hash table. Called at init time.
 void TBTables::add(const std::vector<PieceType>& pieces) {
-    if (sizeof(char*) < 8 && pieces.size() >= 6)
-        return; // Not enough address space to support 6-men TB on 32-bit OS
 
     std::string code;
 
@@ -1002,7 +1000,7 @@ uint8_t* set_sizes(PairsData* d, uint8_t* data) {
     // so that d->lowestSym[i] >= d->lowestSym[i+1] (when read as LittleEndian).
     // Starting from this we compute a base64[] table indexed by symbol length
     // and containing 64 bit values so that d->base64[i] >= d->base64[i+1].
-    // See http://www.eecs.harvard.edu/~michaelm/E210/huffman.pdf
+    // See https://en.wikipedia.org/wiki/Huffman_coding
     for (int i = d->base64.size() - 2; i >= 0; --i) {
         d->base64[i] = (d->base64[i + 1] + number<Sym, LittleEndian>(&d->lowestSym[i])
                                          - number<Sym, LittleEndian>(&d->lowestSym[i + 1])) / 2;
@@ -1143,7 +1141,7 @@ void* mapped(TBTable<Type>& e, const Position& pos) {
     if (e.ready.load(std::memory_order_acquire))
         return e.baseAddress; // Could be nullptr if file does not exist
 
-    std::unique_lock<std::mutex> lk(mutex);
+    std::scoped_lock<std::mutex> lk(mutex);
 
     if (e.ready.load(std::memory_order_relaxed)) // Recheck under lock
         return e.baseAddress;
@@ -1442,7 +1440,7 @@ WDLScore Tablebases::probe_wdl(Position& pos, ProbeState* result) {
 // If n = 100 immediately after a capture or pawn move, then the position
 // is also certainly a win, and during the whole phase until the next
 // capture or pawn move, the inequality to be preserved is
-// dtz + 50-movecounter <= 100.
+// dtz + 50-move-counter <= 100.
 //
 // In short, if a move is available resulting in dtz + 50-move-counter <= 99,
 // then do not accept moves leading to dtz + 50-move-counter == 100.

DroidFishApp/src/main/cpp/stockfish/syzygy/tbprobe.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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

DroidFishApp/src/main/cpp/stockfish/thread.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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

DroidFishApp/src/main/cpp/stockfish/thread.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -73,6 +73,7 @@ public:
   CapturePieceToHistory captureHistory;
   ContinuationHistory continuationHistory[2][2];
   Score contempt;
+  int failedHighCnt;
 };
 
 

DroidFishApp/src/main/cpp/stockfish/thread_win32_osx.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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

DroidFishApp/src/main/cpp/stockfish/timeman.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -75,7 +75,7 @@ void TimeManagement::init(Search::LimitsType& limits, Color us, int ply) {
   // game time for the current move, so also cap to 20% of available game time.
   if (limits.movestogo == 0)
   {
-      optScale = std::min(0.008 + std::pow(ply + 3.0, 0.5) / 250.0,
+      optScale = std::min(0.0084 + std::pow(ply + 3.0, 0.5) * 0.0042,
                            0.2 * limits.time[us] / double(timeLeft));
       maxScale = std::min(7.0, 4.0 + ply / 12.0);
   }

DroidFishApp/src/main/cpp/stockfish/timeman.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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

DroidFishApp/src/main/cpp/stockfish/tt.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -123,7 +123,7 @@ TTEntry* TranspositionTable::probe(const Key key, bool& found) const {
   for (int i = 0; i < ClusterSize; ++i)
       if (tte[i].key16 == key16 || !tte[i].depth8)
       {
-          tte[i].genBound8 = uint8_t(generation8 | (tte[i].genBound8 & 0x7)); // Refresh
+          tte[i].genBound8 = uint8_t(generation8 | (tte[i].genBound8 & (GENERATION_DELTA - 1))); // Refresh
 
           return found = (bool)tte[i].depth8, &tte[i];
       }
@@ -132,11 +132,12 @@ TTEntry* TranspositionTable::probe(const Key key, bool& found) const {
   TTEntry* replace = tte;
   for (int i = 1; i < ClusterSize; ++i)
       // Due to our packed storage format for generation and its cyclic
-      // nature we add 263 (256 is the modulus plus 7 to keep the unrelated
+      // nature we add GENERATION_CYCLE (256 is the modulus, plus what
-      // lowest three bits from affecting the result) to calculate the entry
+      // is needed to keep the unrelated lowest n bits from affecting
-      // age correctly even after generation8 overflows into the next cycle.
+      // the result) to calculate the entry age correctly even after
-      if (  replace->depth8 - ((263 + generation8 - replace->genBound8) & 0xF8)
+      // generation8 overflows into the next cycle.
-          >   tte[i].depth8 - ((263 + generation8 -   tte[i].genBound8) & 0xF8))
+      if (  replace->depth8 - ((GENERATION_CYCLE + generation8 - replace->genBound8) & GENERATION_MASK)
+          >   tte[i].depth8 - ((GENERATION_CYCLE + generation8 -   tte[i].genBound8) & GENERATION_MASK))
           replace = &tte[i];
 
   return found = false, replace;
@@ -151,7 +152,7 @@ int TranspositionTable::hashfull() const {
   int cnt = 0;
   for (int i = 0; i < 1000; ++i)
       for (int j = 0; j < ClusterSize; ++j)
-          cnt += table[i].entry[j].depth8 && (table[i].entry[j].genBound8 & 0xF8) == generation8;
+          cnt += table[i].entry[j].depth8 && (table[i].entry[j].genBound8 & GENERATION_MASK) == generation8;
 
   return cnt / ClusterSize;
 }

DroidFishApp/src/main/cpp/stockfish/tt.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -72,9 +72,15 @@ class TranspositionTable {
 
   static_assert(sizeof(Cluster) == 32, "Unexpected Cluster size");
 
+  // Constants used to refresh the hash table periodically
+  static constexpr unsigned GENERATION_BITS  = 3;                                // nb of bits reserved for other things
+  static constexpr int      GENERATION_DELTA = (1 << GENERATION_BITS);           // increment for generation field
+  static constexpr int      GENERATION_CYCLE = 255 + (1 << GENERATION_BITS);     // cycle length
+  static constexpr int      GENERATION_MASK  = (0xFF << GENERATION_BITS) & 0xFF; // mask to pull out generation number
+
 public:
  ~TranspositionTable() { aligned_large_pages_free(table); }
-  void new_search() { generation8 += 8; } // Lower 3 bits are used by PV flag and Bound
+  void new_search() { generation8 += GENERATION_DELTA; } // Lower bits are used for other things
   TTEntry* probe(const Key key, bool& found) const;
   int hashfull() const;
   void resize(size_t mbSize);

DroidFishApp/src/main/cpp/stockfish/tune.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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

DroidFishApp/src/main/cpp/stockfish/tune.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -130,9 +130,9 @@ class Tune {
     SetRange range;
   };
 
-  // Our facilty to fill the container, each Entry corresponds to a parameter to tune.
+  // Our facility to fill the container, each Entry corresponds to a parameter
-  // We use variadic templates to deal with an unspecified number of entries, each one
+  // to tune. We use variadic templates to deal with an unspecified number of
-  // of a possible different type.
+  // entries, each one of a possible different type.
   static std::string next(std::string& names, bool pop = true);
 
   int add(const SetRange&, std::string&&) { return 0; }

DroidFishApp/src/main/cpp/stockfish/types.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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
@@ -57,6 +57,12 @@
 /// _WIN32             Building on Windows (any)
 /// _WIN64             Building on Windows 64 bit
 
+#if defined(__GNUC__ ) && (__GNUC__ < 9 || (__GNUC__ == 9 && __GNUC_MINOR__ <= 2)) && defined(_WIN32) && !defined(__clang__)
+#define ALIGNAS_ON_STACK_VARIABLES_BROKEN
+#endif
+
+#define ASSERT_ALIGNED(ptr, alignment) assert(reinterpret_cast<uintptr_t>(ptr) % alignment == 0)
+
 #if defined(_WIN64) && defined(_MSC_VER) // No Makefile used
 #  include <intrin.h> // Microsoft header for _BitScanForward64()
 #  define IS_64BIT
@@ -107,7 +113,7 @@ constexpr int MAX_PLY   = 246;
 /// bit  6-11: origin square (from 0 to 63)
 /// bit 12-13: promotion piece type - 2 (from KNIGHT-2 to QUEEN-2)
 /// bit 14-15: special move flag: promotion (1), en passant (2), castling (3)
-/// NOTE: EN-PASSANT bit is set only when a pawn can be captured
+/// NOTE: en passant bit is set only when a pawn can be captured
 ///
 /// Special cases are MOVE_NONE and MOVE_NULL. We can sneak these in because in
 /// any normal move destination square is always different from origin square
@@ -121,7 +127,7 @@ enum Move : int {
 enum MoveType {
   NORMAL,
   PROMOTION = 1 << 14,
-  ENPASSANT = 2 << 14,
+  EN_PASSANT = 2 << 14,
   CASTLING  = 3 << 14
 };
 
@@ -196,8 +202,8 @@ enum PieceType {
 
 enum Piece {
   NO_PIECE,
-  W_PAWN = 1, W_KNIGHT, W_BISHOP, W_ROOK, W_QUEEN, W_KING,
+  W_PAWN = PAWN,     W_KNIGHT, W_BISHOP, W_ROOK, W_QUEEN, W_KING,
-  B_PAWN = 9, B_KNIGHT, B_BISHOP, B_ROOK, B_QUEEN, B_KING,
+  B_PAWN = PAWN + 8, B_KNIGHT, B_BISHOP, B_ROOK, B_QUEEN, B_KING,
   PIECE_NB = 16
 };
 

DroidFishApp/src/main/cpp/stockfish/uci.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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

DroidFishApp/src/main/cpp/stockfish/uci.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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

DroidFishApp/src/main/cpp/stockfish/ucioption.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2021 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

DroidFishApp/src/main/java/org/petero/droidfish/engine/InternalStockFish.java

@@ -36,7 +36,7 @@ import org.petero.droidfish.EngineOptions;
 
 /** Stockfish engine running as process, started from assets resource. */
 public class InternalStockFish extends ExternalEngine {
-    private static final String defaultNet = "nn-baeb9ef2d183.nnue";
+    private static final String defaultNet = "nn-62ef826d1a6d.nnue";
     private static final String netOption = "evalfile";
     private File defaultNetFile; // To get the full path of the copied default network file