#include <cassert>
+#include "bitcount.h"
#include "movegen.h"
// Simple macro to wrap a very common while loop, no facny, no flexibility,
/// generate_captures generates() all pseudo-legal captures and queen
-/// promotions. The return value is the number of moves generated.
+/// promotions. The return value is the number of moves generated.
int generate_captures(const Position& pos, MoveStack* mlist) {
assert(pinned == pos.pinned_pieces(pos.side_to_move()));
Color us = pos.side_to_move();
- Color them = opposite_color(us);
Square from = move_from(m);
Piece pc = pos.piece_on(from);
if (color_of_piece(pc) != us)
return false;
+ Color them = opposite_color(us);
Square to = move_to(m);
// En passant moves
// Direct checks. These are possible only for pawns on neighboring files
// and in the two ranks that, after the push, are in front of the enemy king.
b1 = pawns & neighboring_files_bb(ksq) & ~dc;
- b2 = rank_bb(ksq + 2 * TDELTA_S) | rank_bb(ksq + 3 * TDELTA_S);
- b1 &= b2;
- if (!b1)
+
+ // We can get false positives if (ksq + x) is not in [0,63] range but
+ // is not a problem, they will be filtered out later.
+ b2 = b1 & (rank_bb(ksq + 2 * TDELTA_S) | rank_bb(ksq + 3 * TDELTA_S));
+ if (!b2)
return mlist;
// Direct checks, single pawn pushes
// Direct checks
b = target & ~dc;
- if (Piece == KING || !b)
- return mlist;
-
- Bitboard checkSqs = pos.piece_attacks<Piece>(ksq) & pos.empty_squares();
- if (!checkSqs)
- return mlist;
-
- while (b)
+ if (Piece != KING || b)
{
- Square from = pop_1st_bit(&b);
- if ( (Piece == QUEEN && !(QueenPseudoAttacks[from] & checkSqs))
- || (Piece == ROOK && !(RookPseudoAttacks[from] & checkSqs))
- || (Piece == BISHOP && !(BishopPseudoAttacks[from] & checkSqs)))
- continue;
+ Bitboard checkSqs = pos.piece_attacks<Piece>(ksq) & pos.empty_squares();
+ if (!checkSqs)
+ return mlist;
- Bitboard bb = pos.piece_attacks<Piece>(from) & checkSqs;
- SERIALIZE_MOVES(bb);
+ while (b)
+ {
+ Square from = pop_1st_bit(&b);
+ if ( (Piece == QUEEN && !(QueenPseudoAttacks[from] & checkSqs))
+ || (Piece == ROOK && !(RookPseudoAttacks[from] & checkSqs))
+ || (Piece == BISHOP && !(BishopPseudoAttacks[from] & checkSqs)))
+ continue;
+
+ Bitboard bb = pos.piece_attacks<Piece>(from) & checkSqs;
+ SERIALIZE_MOVES(bb);
+ }
}
return mlist;
}