Retire Position::move_is_legal()

[stockfish] / src / position.cpp

diff --git a/src/position.cpp b/src/position.cpp
index 0ed2fff4db4007737aeab8216ebc4a51e87d350f..ef5fd97091cc4f0f478b41954090ba8e72a1799f 100644 (file)
--- a/src/position.cpp
+++ b/src/position.cpp
@@ -521,20 +521,6 @@ bool Position::pl_move_is_legal(Move m, Bitboard pinned) const {
 }
 
 
-/// Position::move_is_legal() takes a random move and tests whether the move
-/// is legal. This version is not very fast and should be used only in non
-/// time-critical paths.
-
-bool Position::move_is_legal(const Move m) const {
-
-  for (MoveList<LEGAL> ml(*this); !ml.end(); ++ml)
-      if (ml.move() == m)
-          return true;
-
-  return false;
-}
-
-
 /// Position::is_pseudo_legal() takes a random move and tests whether the move
 /// is pseudo legal. It is used to validate moves from TT that can be corrupted
 /// due to SMP concurrent access or hash position key aliasing.
@@ -542,14 +528,13 @@ bool Position::move_is_legal(const Move m) const {
 bool Position::is_pseudo_legal(const Move m) const {
 
   Color us = sideToMove;
-  Color them = ~sideToMove;
   Square from = from_sq(m);
   Square to = to_sq(m);
   Piece pc = piece_moved(m);
 
   // Use a slower but simpler function for uncommon cases
   if (type_of(m) != NORMAL)
-      return move_is_legal(m);
+      return MoveList<LEGAL>(*this).contains(m);
 
   // Is not a promotion, so promotion piece must be empty
   if (promotion_type(m) - 2 != NO_PIECE_TYPE)
@@ -587,7 +572,7 @@ bool Position::is_pseudo_legal(const Move m) const {
       case DELTA_SE:
       // Capture. The destination square must be occupied by an enemy
       // piece (en passant captures was handled earlier).
-      if (piece_on(to) == NO_PIECE || color_of(piece_on(to)) != them)
+      if (piece_on(to) == NO_PIECE || color_of(piece_on(to)) != ~us)
           return false;
 
       // From and to files must be one file apart, avoids a7h5
@@ -636,14 +621,12 @@ bool Position::is_pseudo_legal(const Move m) const {
   {
       if (type_of(pc) != KING)
       {
-          Bitboard b = checkers();
-          Square checksq = pop_lsb(&b);
-
-          if (b) // double check ? In this case a king move is required
+          // Double check? In this case a king move is required
+          if (more_than_one(checkers()))
               return false;
 
           // Our move must be a blocking evasion or a capture of the checking piece
-          if (!((between_bb(checksq, king_square(us)) | checkers()) & to))
+          if (!((between_bb(lsb(checkers()), king_square(us)) | checkers()) & to))
               return false;
       }
       // In case of king moves under check we have to remove king so to catch