+
+ if (pm) // promotion ?
+ {
+ PieceType promotion = move_promotion_piece(m);
+
+ assert(promotion >= KNIGHT && promotion <= QUEEN);
+
+ // Insert promoted piece instead of pawn
+ clear_bit(&(byTypeBB[PAWN]), to);
+ set_bit(&(byTypeBB[promotion]), to);
+ board[to] = piece_of_color_and_type(us, promotion);
+
+ // Update piece counts
+ pieceCount[us][promotion]++;
+ pieceCount[us][PAWN]--;
+
+ // Update material key
+ st->materialKey ^= zobrist[us][PAWN][pieceCount[us][PAWN]];
+ st->materialKey ^= zobrist[us][promotion][pieceCount[us][promotion]-1];
+
+ // Update piece lists, move the last pawn at index[to] position
+ // and shrink the list. Add a new promotion piece to the list.
+ Square lastPawnSquare = pieceList[us][PAWN][pieceCount[us][PAWN]];
+ index[lastPawnSquare] = index[to];
+ pieceList[us][PAWN][index[lastPawnSquare]] = lastPawnSquare;
+ pieceList[us][PAWN][pieceCount[us][PAWN]] = SQ_NONE;
+ index[to] = pieceCount[us][promotion] - 1;
+ pieceList[us][promotion][index[to]] = to;
+
+ // Partially revert hash keys update
+ key ^= zobrist[us][PAWN][to] ^ zobrist[us][promotion][to];
+ st->pawnKey ^= zobrist[us][PAWN][to];
+
+ // Partially revert and update incremental scores
+ st->value -= pst(us, PAWN, to);
+ st->value += pst(us, promotion, to);
+
+ // Update material
+ st->npMaterial[us] += piece_value_midgame(promotion);
+ }