X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.cpp;h=93c42291b658d6d90ec9236d2a8642c3073c6037;hp=ce48e33fb6fedd5721b7a890da8665c7cda85046;hb=3e40bd0648ab69c04e37da50fd3f3d4beb072df2;hpb=5c81602d14539f8259a715477315e28b5de7cb54

diff --git a/src/position.cpp b/src/position.cpp
index ce48e33f..93c42291 100644
--- a/src/position.cpp
+++ b/src/position.cpp
@@ -35,13 +35,13 @@
 #include "san.h"
 #include "ucioption.h"
 
+using std::string;
+
 
 ////
 //// Variables
 ////
 
-extern SearchStack EmptySearchStack;
-
 int Position::castleRightsMask[64];
 
 Key Position::zobrist[2][8][64];
@@ -65,7 +65,7 @@ Position::Position(const Position& pos) {
   copy(pos);
 }
 
-Position::Position(const std::string& fen) {
+Position::Position(const string& fen) {
   from_fen(fen);
 }
 
@@ -74,9 +74,9 @@ Position::Position(const std::string& fen) {
 /// string. This function is not very robust - make sure that input FENs are
 /// correct (this is assumed to be the responsibility of the GUI).
 
-void Position::from_fen(const std::string& fen) {
+void Position::from_fen(const string& fen) {
 
-  static const std::string pieceLetters = "KQRBNPkqrbnp";
+  static const string pieceLetters = "KQRBNPkqrbnp";
   static const Piece pieces[] = { WK, WQ, WR, WB, WN, WP, BK, BQ, BR, BB, BN, BP };
 
   clear();
@@ -100,7 +100,7 @@ void Position::from_fen(const std::string& fen) {
           continue;
       }
       size_t idx = pieceLetters.find(fen[i]);
-      if (idx == std::string::npos)
+      if (idx == string::npos)
       {
            std::cout << "Error in FEN at character " << i << std::endl;
            return;
@@ -213,18 +213,18 @@ void Position::from_fen(const std::string& fen) {
   st->materialKey = compute_material_key();
   st->mgValue = compute_value<MidGame>();
   st->egValue = compute_value<EndGame>();
-  npMaterial[WHITE] = compute_non_pawn_material(WHITE);
-  npMaterial[BLACK] = compute_non_pawn_material(BLACK);
+  st->npMaterial[WHITE] = compute_non_pawn_material(WHITE);
+  st->npMaterial[BLACK] = compute_non_pawn_material(BLACK);
 }
 
 
 /// Position::to_fen() converts the position object to a FEN string. This is
 /// probably only useful for debugging.
 
-const std::string Position::to_fen() const {
+const string Position::to_fen() const {
 
-  static const std::string pieceLetters = " PNBRQK  pnbrqk";
-  std::string fen;
+  static const string pieceLetters = " PNBRQK  pnbrqk";
+  string fen;
   int skip;
 
   for (Rank rank = RANK_8; rank >= RANK_1; rank--)
@@ -274,7 +274,7 @@ const std::string Position::to_fen() const {
 
 void Position::print(Move m) const {
 
-  static const std::string pieceLetters = " PNBRQK  PNBRQK .";
+  static const string pieceLetters = " PNBRQK  PNBRQK .";
 
   // Check for reentrancy, as example when called from inside
   // MovePicker that is used also here in move_to_san()
@@ -286,7 +286,7 @@ void Position::print(Move m) const {
   std::cout << std::endl;
   if (m != MOVE_NONE)
   {
-      std::string col = (color_of_piece_on(move_from(m)) == BLACK ? ".." : "");
+      string col = (color_of_piece_on(move_from(m)) == BLACK ? ".." : "");
       std::cout << "Move is: " << col << move_to_san(*this, m) << std::endl;
   }
   for (Rank rank = RANK_8; rank >= RANK_1; rank--)
@@ -377,9 +377,7 @@ Bitboard Position::discovered_check_candidates(Color c) const {
 }
 
 /// Position::attacks_to() computes a bitboard containing all pieces which
-/// attacks a given square. There are two versions of this function: One
-/// which finds attackers of both colors, and one which only finds the
-/// attackers for one side.
+/// attacks a given square.
 
 Bitboard Position::attacks_to(Square s) const {
 
@@ -658,6 +656,7 @@ inline void Position::update_checkers(Bitboard* pCheckersBB, Square ksq, Square
   const bool Rook   = (Piece == QUEEN || Piece == ROOK);
   const bool Slider = Bishop || Rook;
 
+  // Direct checks
   if (  (   (Bishop && bit_is_set(BishopPseudoAttacks[ksq], to))
          || (Rook   && bit_is_set(RookPseudoAttacks[ksq], to)))
       && bit_is_set(piece_attacks<Piece>(ksq), to)) // slow, try to early skip
@@ -668,6 +667,7 @@ inline void Position::update_checkers(Bitboard* pCheckersBB, Square ksq, Square
            && bit_is_set(piece_attacks<Piece>(ksq), to))
       set_bit(pCheckersBB, to);
 
+  // Discovery checks
   if (Piece != QUEEN && bit_is_set(dcCandidates, from))
   {
       if (Piece != ROOK)
@@ -701,6 +701,7 @@ void Position::do_move(Move m, StateInfo& newSt, Bitboard dcCandidates) {
     int castleRights, rule50;
     Square epSquare;
     Value mgValue, egValue;
+    Value npMaterial[2];
   };
 
   memcpy(&newSt, st, sizeof(ReducedStateInfo));
@@ -740,12 +741,11 @@ void Position::do_move(Move m, StateInfo& newSt, Bitboard dcCandidates) {
       do_capture_move(st->capture, them, to);
 
     // Move the piece
-    clear_bit(&(byColorBB[us]), from);
-    clear_bit(&(byTypeBB[piece]), from);
-    clear_bit(&(byTypeBB[0]), from); // HACK: byTypeBB[0] == occupied squares
-    set_bit(&(byColorBB[us]), to);
-    set_bit(&(byTypeBB[piece]), to);
-    set_bit(&(byTypeBB[0]), to); // HACK: byTypeBB[0] == occupied squares
+    Bitboard move_bb = make_move_bb(from, to);
+    do_move_bb(&(byColorBB[us]), move_bb);
+    do_move_bb(&(byTypeBB[piece]), move_bb);
+    do_move_bb(&(byTypeBB[0]), move_bb); // HACK: byTypeBB[0] == occupied squares
+
     board[to] = board[from];
     board[from] = EMPTY;
 
@@ -837,6 +837,7 @@ void Position::do_capture_move(PieceType capture, Color them, Square to) {
     // Remove captured piece
     clear_bit(&(byColorBB[them]), to);
     clear_bit(&(byTypeBB[capture]), to);
+    clear_bit(&(byTypeBB[0]), to);
 
     // Update hash key
     st->key ^= zobrist[them][capture][to];
@@ -851,7 +852,7 @@ void Position::do_capture_move(PieceType capture, Color them, Square to) {
 
     // Update material
     if (capture != PAWN)
-        npMaterial[them] -= piece_value_midgame(capture);
+        st->npMaterial[them] -= piece_value_midgame(capture);
 
     // Update material hash key
     st->materialKey ^= zobMaterial[them][capture][pieceCount[them][capture]];
@@ -990,7 +991,7 @@ void Position::do_promotion_move(Move m) {
   st->capture = type_of_piece_on(to);
 
   if (st->capture)
-    do_capture_move(st->capture, them, to);
+      do_capture_move(st->capture, them, to);
 
   // Remove pawn
   clear_bit(&(byColorBB[us]), from);
@@ -1033,7 +1034,7 @@ void Position::do_promotion_move(Move m) {
   st->egValue += pst<EndGame>(us, promotion, to);
 
   // Update material
-  npMaterial[us] += piece_value_midgame(promotion);
+  st->npMaterial[us] += piece_value_midgame(promotion);
 
   // Clear the en passant square
   if (st->epSquare != SQ_NONE)
@@ -1169,17 +1170,13 @@ void Position::undo_move(Move m) {
       assert(color_of_piece_on(to) == us);
 
       // Put the piece back at the source square
+      Bitboard move_bb = make_move_bb(to, from);
       piece = type_of_piece_on(to);
-      set_bit(&(byColorBB[us]), from);
-      set_bit(&(byTypeBB[piece]), from);
-      set_bit(&(byTypeBB[0]), from); // HACK: byTypeBB[0] == occupied squares
+      do_move_bb(&(byColorBB[us]), move_bb);
+      do_move_bb(&(byTypeBB[piece]), move_bb);
+      do_move_bb(&(byTypeBB[0]), move_bb); // HACK: byTypeBB[0] == occupied squares
       board[from] = piece_of_color_and_type(us, piece);
 
-      // Clear the destination square
-      clear_bit(&(byColorBB[us]), to);
-      clear_bit(&(byTypeBB[piece]), to);
-      clear_bit(&(byTypeBB[0]), to); // HACK: byTypeBB[0] == occupied squares
-
       // If the moving piece was a king, update the king square
       if (piece == KING)
           kingSquare[us] = from;
@@ -1192,16 +1189,12 @@ void Position::undo_move(Move m) {
       {
           assert(st->capture != KING);
 
-          // Replace the captured piece
+          // Restore the captured piece
           set_bit(&(byColorBB[them]), to);
           set_bit(&(byTypeBB[st->capture]), to);
           set_bit(&(byTypeBB[0]), to);
           board[to] = piece_of_color_and_type(them, st->capture);
 
-          // Update material
-          if (st->capture != PAWN)
-              npMaterial[them] += piece_value_midgame(st->capture);
-
           // Update piece list
           pieceList[them][st->capture][pieceCount[them][st->capture]] = to;
           index[to] = pieceCount[them][st->capture];
@@ -1323,9 +1316,6 @@ void Position::undo_promotion_move(Move m) {
   set_bit(&(byTypeBB[0]), from); // HACK: byTypeBB[0] == occupied squares
   board[from] = piece_of_color_and_type(us, PAWN);
 
-  // Update material
-  npMaterial[us] -= piece_value_midgame(promotion);
-
   // Update piece list
   pieceList[us][PAWN][pieceCount[us][PAWN]] = from;
   index[from] = pieceCount[us][PAWN];
@@ -1347,11 +1337,6 @@ void Position::undo_promotion_move(Move m) {
       set_bit(&(byTypeBB[0]), to); // HACK: byTypeBB[0] == occupied squares
       board[to] = piece_of_color_and_type(them, st->capture);
 
-      // Update material. Because the move is a promotion move, we know
-      // that the captured piece cannot be a pawn.
-      assert(st->capture != PAWN);
-      npMaterial[them] += piece_value_midgame(st->capture);
-
       // Update piece list
       pieceList[them][st->capture][pieceCount[them][st->capture]] = to;
       index[to] = pieceCount[them][st->capture];
@@ -1404,13 +1389,13 @@ void Position::undo_ep_move(Move m) {
   set_bit(&(byTypeBB[0]), from);
   board[from] = piece_of_color_and_type(us, PAWN);
 
-  // Update piece list:
+  // Update piece list
   pieceList[us][PAWN][index[to]] = from;
   index[from] = index[to];
   pieceList[them][PAWN][pieceCount[them][PAWN]] = capsq;
   index[capsq] = pieceCount[them][PAWN];
 
-  // Update piece count:
+  // Update piece count
   pieceCount[them][PAWN]++;
 }
 
@@ -1424,12 +1409,13 @@ void Position::do_null_move(StateInfo& backupSt) {
   assert(!is_check());
 
   // Back up the information necessary to undo the null move to the supplied
-  // StateInfo object. In the case of a null move, the only thing we need to
-  // remember is the last move made and the en passant square.
+  // StateInfo object.
   // Note that differently from normal case here backupSt is actually used as
   // a backup storage not as a new state to be used.
-  backupSt.lastMove = st->lastMove;
   backupSt.epSquare = st->epSquare;
+  backupSt.key = st->key;
+  backupSt.mgValue = st->mgValue;
+  backupSt.egValue = st->egValue;
   backupSt.previous = st->previous;
   st->previous = &backupSt;
 
@@ -1462,21 +1448,16 @@ void Position::undo_null_move() {
   assert(!is_check());
 
   // Restore information from the our backup StateInfo object
-  st->lastMove = st->previous->lastMove;
   st->epSquare = st->previous->epSquare;
+  st->key = st->previous->key;
+  st->mgValue = st->previous->mgValue;
+  st->egValue = st->previous->egValue;
   st->previous = st->previous->previous;
 
-  if (st->epSquare != SQ_NONE)
-      st->key ^= zobEp[st->epSquare];
-
   // Update the necessary information
   sideToMove = opposite_color(sideToMove);
   st->rule50--;
   gamePly--;
-  st->key ^= zobSideToMove;
-
-  st->mgValue += (sideToMove == WHITE)? TempoValueMidgame : -TempoValueMidgame;
-  st->egValue += (sideToMove == WHITE)? TempoValueEndgame : -TempoValueEndgame;
 
   assert(is_ok());
 }
@@ -2043,8 +2024,8 @@ void Position::flipped_copy(const Position &pos) {
   st->egValue = compute_value<EndGame>();
 
   // Material
-  npMaterial[WHITE] = compute_non_pawn_material(WHITE);
-  npMaterial[BLACK] = compute_non_pawn_material(BLACK);
+  st->npMaterial[WHITE] = compute_non_pawn_material(WHITE);
+  st->npMaterial[BLACK] = compute_non_pawn_material(BLACK);
 
   assert(is_ok());
 }
@@ -2180,10 +2161,10 @@ bool Position::is_ok(int* failedStep) const {
   if (failedStep) (*failedStep)++;
   if (debugNonPawnMaterial)
   {
-      if (npMaterial[WHITE] != compute_non_pawn_material(WHITE))
+      if (st->npMaterial[WHITE] != compute_non_pawn_material(WHITE))
           return false;
 
-      if (npMaterial[BLACK] != compute_non_pawn_material(BLACK))
+      if (st->npMaterial[BLACK] != compute_non_pawn_material(BLACK))
           return false;
   }