Merge official-stockfish/master

bench: 5115004

diff --cc Readme.md
Simple merge

diff --cc src/search.cpp
index 6ad2ab9,b0bcc57..c68080d
--- 1/src/search.cpp
--- 2/src/search.cpp
+++ b/src/search.cpp
@@@ -448,7 -428,7 +448,7 @@@ void Thread::search() 
            if (rootDepth >= 4)
            {
                Value previousScore = rootMoves[pvIdx].previousScore;
-               delta = Value(21 * (1 + rootPos.captures_to_hand()) + abs(previousScore) / 128);
 -              delta = Value(21 + abs(previousScore) / 256);
++              delta = Value(21 * (1 + rootPos.captures_to_hand()) + abs(previousScore) / 256);
                alpha = std::max(previousScore - delta,-VALUE_INFINITE);
                beta  = std::min(previousScore + delta, VALUE_INFINITE);
  
@@@ -842,37 -815,28 +842,37 @@@ namespace 
      improving =  (ss-2)->staticEval == VALUE_NONE ? (ss->staticEval >= (ss-4)->staticEval
                || (ss-4)->staticEval == VALUE_NONE) : ss->staticEval >= (ss-2)->staticEval;
  
 +    // Skip early pruning in case of mandatory capture
 +    if (pos.must_capture() && MoveList<CAPTURES>(pos).size())
 +        goto moves_loop;
 +
      // Step 8. Futility pruning: child node (~30 Elo)
      if (   !PvNode
-         &&  depth < 7
+         &&  depth < 6
 -        &&  eval - futility_margin(depth, improving) >= beta
 +        && !(   pos.extinction_value() == -VALUE_MATE
 +             && pos.extinction_piece_types().find(ALL_PIECES) == pos.extinction_piece_types().end())
 +        && (pos.checking_permitted() || !pos.capture_the_flag_piece())
 +        &&  eval - futility_margin(depth, improving) * (1 + pos.check_counting()) >= beta
          &&  eval < VALUE_KNOWN_WIN) // Do not return unproven wins
          return eval;
  
      // Step 9. Null move search with verification search (~40 Elo)
      if (   !PvNode
          && (ss-1)->currentMove != MOVE_NULL
-         && (ss-1)->statScore < 22661
+         && (ss-1)->statScore < 23405
          &&  eval >= beta
          &&  eval >= ss->staticEval
-         &&  ss->staticEval >= beta - 33 * depth + 299 - improving * 30
+         &&  ss->staticEval >= beta - 32 * depth + 317 - improving * 30
          && !excludedMove
          &&  pos.non_pawn_material(us)
 +        && (pos.pieces(~us) ^ pos.pieces(~us, PAWN))
 +        && (pos.pieces() ^ pos.pieces(BREAKTHROUGH_PIECE) ^ pos.pieces(CLOBBER_PIECE))
          && (ss->ply >= thisThread->nmpMinPly || us != thisThread->nmpColor))
      {
          assert(eval - beta >= 0);
  
          // Null move dynamic reduction based on depth and value
-         Depth R = (835 - 150 * !pos.checking_permitted() + 70 * depth) / 256 + std::min(int(eval - beta) / 185, 3);
 -        Depth R = (854 + 68 * depth) / 258 + std::min(int(eval - beta) / 192, 3);
++        Depth R = (854 - 150 * !pos.checking_permitted() + 68 * depth) / 258 + std::min(int(eval - beta) / 192, 3);
  
          ss->currentMove = MOVE_NULL;
          ss->continuationHistory = &thisThread->continuationHistory[0][0][NO_PIECE][0];
@@@ -913,10 -877,9 +913,10 @@@
      // much above beta, we can (almost) safely prune the previous move.
      if (   !PvNode
          &&  depth >= 5
 +        &&  (pos.pieces() ^ pos.pieces(CLOBBER_PIECE))
          &&  abs(beta) < VALUE_MATE_IN_MAX_PLY)
      {
-         Value raisedBeta = std::min(beta + (191 + 20 * !!pos.capture_the_flag_piece()) * (1 + pos.check_counting() + (pos.extinction_value() != VALUE_NONE)) - 46 * improving, VALUE_INFINITE);
 -        Value raisedBeta = std::min(beta + 189 - 45 * improving, VALUE_INFINITE);
++        Value raisedBeta = std::min(beta + (189 + 20 * !!pos.capture_the_flag_piece()) * (1 + pos.check_counting() + (pos.extinction_value() != VALUE_NONE)) - 45 * improving, VALUE_INFINITE);
          MovePicker mp(pos, ttMove, raisedBeta - ss->staticEval, &thisThread->captureHistory);
          int probCutCount = 0;
  
@@@ -1042,18 -1003,14 +1042,17 @@@ moves_loop: // When in check, search st
                // Futility pruning: parent node (~2 Elo)
                if (   lmrDepth < 6
                    && !inCheck
 +                  && !(   pos.extinction_value() == -VALUE_MATE
 +                       && pos.extinction_piece_types().find(ALL_PIECES) == pos.extinction_piece_types().end())
-                   && ss->staticEval + 250 + 211 * lmrDepth <= alpha)
+                   && ss->staticEval + 255 + 182 * lmrDepth <= alpha)
                    continue;
  
                // Prune moves with negative SEE (~10 Elo)
-               if (!pos.must_capture() && !pos.see_ge(move, Value(-(31 - std::min(lmrDepth, 18)) * lmrDepth * lmrDepth)))
 -              if (!pos.see_ge(move, Value(-(32 - std::min(lmrDepth, 18)) * lmrDepth * lmrDepth)))
++              if (!pos.must_capture() && !pos.see_ge(move, Value(-(32 - std::min(lmrDepth, 18)) * lmrDepth * lmrDepth)))
                    continue;
            }
-           else if (  !(givesCheck && extension)
-                    && !pos.must_capture()
-                    && !pos.see_ge(move, Value(-199 - 120 * pos.captures_to_hand()) * depth)) // (~20 Elo)
 -          else if (!pos.see_ge(move, Value(-194) * depth)) // (~20 Elo)
++          else if (   !pos.must_capture()
++                   && !pos.see_ge(move, Value(-194 - 120 * pos.captures_to_hand()) * depth)) // (~20 Elo)
                    continue;
        }
  
@@@ -1153,8 -1104,7 +1152,8 @@@
                || moveCountPruning
                || ss->staticEval + PieceValue[EG][pos.captured_piece()] <= alpha
                || cutNode
-               || thisThread->ttHitAverage < 384 * ttHitAverageResolution * ttHitAverageWindow / 1024)
 -              || thisThread->ttHitAverage < 375 * ttHitAverageResolution * ttHitAverageWindow / 1024))
++              || thisThread->ttHitAverage < 375 * ttHitAverageResolution * ttHitAverageWindow / 1024)
 +          && !(pos.must_capture() && MoveList<CAPTURES>(pos).size()))
        {
            Depth r = reduction(improving, depth, moveCount);
  
@@@ -1196,10 -1146,10 +1195,10 @@@
                    r -= 2;
  
                ss->statScore =  thisThread->mainHistory[us][from_to(move)]
 -                             + (*contHist[0])[movedPiece][to_sq(move)]
 -                             + (*contHist[1])[movedPiece][to_sq(move)]
 -                             + (*contHist[3])[movedPiece][to_sq(move)]
 +                             + (*contHist[0])[history_slot(movedPiece)][to_sq(move)]
 +                             + (*contHist[1])[history_slot(movedPiece)][to_sq(move)]
 +                             + (*contHist[3])[history_slot(movedPiece)][to_sq(move)]
-                              - 4729;
+                              - 4926;
  
                // Reset statScore to zero if negative and most stats shows >= 0
                if (    ss->statScore < 0