Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
- Copyright (C) 2015-2018 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad
+ Copyright (C) 2015-2019 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
#include <climits>
#include <cstdint>
#include <cstdlib>
+#include <algorithm>
#if defined(_MSC_VER)
// Disable some silly and noisy warning from MSVC compiler
typedef uint64_t Bitboard;
constexpr int MAX_MOVES = 256;
-constexpr int MAX_PLY = 128;
+constexpr int MAX_PLY = 246;
/// A move needs 16 bits to be stored
///
WHITE, BLACK, COLOR_NB = 2
};
-enum CastlingSide {
- KING_SIDE, QUEEN_SIDE, CASTLING_SIDE_NB = 2
-};
-
-enum CastlingRight {
+enum CastlingRights {
NO_CASTLING,
WHITE_OO,
WHITE_OOO = WHITE_OO << 1,
BLACK_OO = WHITE_OO << 2,
BLACK_OOO = WHITE_OO << 3,
- ANY_CASTLING = WHITE_OO | WHITE_OOO | BLACK_OO | BLACK_OOO,
- CASTLING_RIGHT_NB = 16
-};
-template<Color C, CastlingSide S> struct MakeCastling {
- static constexpr CastlingRight
- right = C == WHITE ? S == QUEEN_SIDE ? WHITE_OOO : WHITE_OO
- : S == QUEEN_SIDE ? BLACK_OOO : BLACK_OO;
+ KING_SIDE = WHITE_OO | BLACK_OO,
+ QUEEN_SIDE = WHITE_OOO | BLACK_OOO,
+ WHITE_CASTLING = WHITE_OO | WHITE_OOO,
+ BLACK_CASTLING = BLACK_OO | BLACK_OOO,
+ ANY_CASTLING = WHITE_CASTLING | BLACK_CASTLING,
+
+ CASTLING_RIGHT_NB = 16
};
enum Phase {
enum ScaleFactor {
SCALE_FACTOR_DRAW = 0,
- SCALE_FACTOR_ONEPAWN = 48,
SCALE_FACTOR_NORMAL = 64,
SCALE_FACTOR_MAX = 128,
SCALE_FACTOR_NONE = 255
VALUE_MATE_IN_MAX_PLY = VALUE_MATE - 2 * MAX_PLY,
VALUE_MATED_IN_MAX_PLY = -VALUE_MATE + 2 * MAX_PLY,
- PawnValueMg = 171, PawnValueEg = 240,
- KnightValueMg = 764, KnightValueEg = 848,
- BishopValueMg = 826, BishopValueEg = 891,
- RookValueMg = 1282, RookValueEg = 1373,
- QueenValueMg = 2500, QueenValueEg = 2670,
+ PawnValueMg = 128, PawnValueEg = 213,
+ KnightValueMg = 781, KnightValueEg = 854,
+ BishopValueMg = 825, BishopValueEg = 915,
+ RookValueMg = 1276, RookValueEg = 1380,
+ QueenValueMg = 2538, QueenValueEg = 2682,
MidgameLimit = 15258, EndgameLimit = 3915
};
extern Value PieceValue[PHASE_NB][PIECE_NB];
-enum Depth : int {
+typedef int Depth;
- ONE_PLY = 1,
+enum : int {
- DEPTH_ZERO = 0 * ONE_PLY,
- DEPTH_QS_CHECKS = 0 * ONE_PLY,
- DEPTH_QS_NO_CHECKS = -1 * ONE_PLY,
- DEPTH_QS_RECAPTURES = -5 * ONE_PLY,
+ DEPTH_QS_CHECKS = 0,
+ DEPTH_QS_NO_CHECKS = -1,
+ DEPTH_QS_RECAPTURES = -5,
- DEPTH_NONE = -6 * ONE_PLY,
- DEPTH_MAX = MAX_PLY * ONE_PLY
+ DEPTH_NONE = -6,
+ DEPTH_OFFSET = DEPTH_NONE,
};
-static_assert(!(ONE_PLY & (ONE_PLY - 1)), "ONE_PLY is not a power of 2");
-
enum Square : int {
SQ_A1, SQ_B1, SQ_C1, SQ_D1, SQ_E1, SQ_F1, SQ_G1, SQ_H1,
SQ_A2, SQ_B2, SQ_C2, SQ_D2, SQ_E2, SQ_F2, SQ_G2, SQ_H2,
};
-/// Score enum stores a middlegame and an endgame value in a single integer
-/// (enum). The least significant 16 bits are used to store the endgame value
-/// and the upper 16 bits are used to store the middlegame value. Take some
-/// care to avoid left-shifting a signed int to avoid undefined behavior.
+/// Score enum stores a middlegame and an endgame value in a single integer (enum).
+/// The least significant 16 bits are used to store the middlegame value and the
+/// upper 16 bits are used to store the endgame value. We have to take care to
+/// avoid left-shifting a signed int to avoid undefined behavior.
enum Score : int { SCORE_ZERO };
constexpr Score make_score(int mg, int eg) {
#define ENABLE_FULL_OPERATORS_ON(T) \
ENABLE_BASE_OPERATORS_ON(T) \
-ENABLE_INCR_OPERATORS_ON(T) \
constexpr T operator*(int i, T d) { return T(i * int(d)); } \
constexpr T operator*(T d, int i) { return T(int(d) * i); } \
constexpr T operator/(T d, int i) { return T(int(d) / i); } \
inline T& operator/=(T& d, int i) { return d = T(int(d) / i); }
ENABLE_FULL_OPERATORS_ON(Value)
-ENABLE_FULL_OPERATORS_ON(Depth)
ENABLE_FULL_OPERATORS_ON(Direction)
ENABLE_INCR_OPERATORS_ON(PieceType)
ENABLE_INCR_OPERATORS_ON(Piece)
-ENABLE_INCR_OPERATORS_ON(Color)
ENABLE_INCR_OPERATORS_ON(Square)
ENABLE_INCR_OPERATORS_ON(File)
ENABLE_INCR_OPERATORS_ON(Rank)
inline Value& operator-=(Value& v, int i) { return v = v - i; }
/// Additional operators to add a Direction to a Square
-inline Square operator+(Square s, Direction d) { return Square(int(s) + int(d)); }
-inline Square operator-(Square s, Direction d) { return Square(int(s) - int(d)); }
-inline Square& operator+=(Square &s, Direction d) { return s = s + d; }
-inline Square& operator-=(Square &s, Direction d) { return s = s - d; }
+constexpr Square operator+(Square s, Direction d) { return Square(int(s) + int(d)); }
+constexpr Square operator-(Square s, Direction d) { return Square(int(s) - int(d)); }
+inline Square& operator+=(Square& s, Direction d) { return s = s + d; }
+inline Square& operator-=(Square& s, Direction d) { return s = s - d; }
/// Only declared but not defined. We don't want to multiply two scores due to
/// a very high risk of overflow. So user should explicitly convert to integer.
assert(eg_value(result) == (i * eg_value(s)));
assert(mg_value(result) == (i * mg_value(s)));
- assert((i == 0) || (result / i) == s );
+ assert((i == 0) || (result / i) == s);
return result;
}
+/// Multiplication of a Score by a boolean
+inline Score operator*(Score s, bool b) {
+ return Score(int(s) * int(b));
+}
+
constexpr Color operator~(Color c) {
return Color(c ^ BLACK); // Toggle color
}
return Square(s ^ SQ_A8); // Vertical flip SQ_A1 -> SQ_A8
}
-constexpr File operator~(File f) {
- return File(f ^ FILE_H); // Horizontal flip FILE_A -> FILE_H
-}
-
constexpr Piece operator~(Piece pc) {
return Piece(pc ^ 8); // Swap color of piece B_KNIGHT -> W_KNIGHT
}
-constexpr CastlingRight operator|(Color c, CastlingSide s) {
- return CastlingRight(WHITE_OO << ((s == QUEEN_SIDE) + 2 * c));
+inline File map_to_queenside(File f) {
+ return std::min(f, File(FILE_H - f)); // Map files ABCDEFGH to files ABCDDCBA
+}
+
+constexpr CastlingRights operator&(Color c, CastlingRights cr) {
+ return CastlingRights((c == WHITE ? WHITE_CASTLING : BLACK_CASTLING) & cr);
}
constexpr Value mate_in(int ply) {
return relative_rank(c, rank_of(s));
}
-inline bool opposite_colors(Square s1, Square s2) {
- int s = int(s1) ^ int(s2);
- return ((s >> 3) ^ s) & 1;
-}
-
constexpr Direction pawn_push(Color c) {
return c == WHITE ? NORTH : SOUTH;
}
return PieceType(((m >> 12) & 3) + KNIGHT);
}
-inline Move make_move(Square from, Square to) {
+constexpr Move make_move(Square from, Square to) {
return Move((from << 6) + to);
}
+constexpr Move reverse_move(Move m) {
+ return make_move(to_sq(m), from_sq(m));
+}
+
template<MoveType T>
constexpr Move make(Square from, Square to, PieceType pt = KNIGHT) {
return Move(T + ((pt - KNIGHT) << 12) + (from << 6) + to);