+// Define a __cpuid() function for gcc compilers, for Intel and MSVC
+// is already available as an intrinsic.
+#if defined(_MSC_VER)
+#include <intrin.h>
+#elif defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
+inline void __cpuid(int CPUInfo[4], int InfoType)
+{
+ int* eax = CPUInfo + 0;
+ int* ebx = CPUInfo + 1;
+ int* ecx = CPUInfo + 2;
+ int* edx = CPUInfo + 3;
+
+ *eax = InfoType;
+ *ecx = 0;
+ __asm__("cpuid" : "=a" (*eax), "=b" (*ebx), "=c" (*ecx), "=d" (*edx)
+ : "0" (*eax), "2" (*ecx));
+}
+#else
+inline void __cpuid(int CPUInfo[4], int)
+{
+ CPUInfo[0] = CPUInfo[1] = CPUInfo[2] = CPUInfo[3] = 0;
+}
+#endif
+
+// Define FORCE_INLINE macro to force inlining overriding compiler choice
+#if defined(_MSC_VER)
+#define FORCE_INLINE __forceinline
+#elif defined(__GNUC__)
+#define FORCE_INLINE inline __attribute__((always_inline))
+#else
+#define FORCE_INLINE inline
+#endif
+
+/// cpu_has_popcnt() detects support for popcnt instruction at runtime
+inline bool cpu_has_popcnt() {
+
+ int CPUInfo[4] = {-1};
+ __cpuid(CPUInfo, 0x00000001);
+ return (CPUInfo[2] >> 23) & 1;
+}
+
+/// CpuHasPOPCNT is a global constant initialized at startup that
+/// is set to true if CPU on which application runs supports popcnt
+/// hardware instruction. Unless USE_POPCNT is not defined.
+#if defined(USE_POPCNT)
+const bool CpuHasPOPCNT = cpu_has_popcnt();
+#else
+const bool CpuHasPOPCNT = false;
+#endif
+
+
+/// CpuIs64Bit is a global constant initialized at compile time that
+/// is set to true if CPU on which application runs is a 64 bits.
+#if defined(IS_64BIT)
+const bool CpuIs64Bit = true;
+#else
+const bool CpuIs64Bit = false;
+#endif
+
+#include <string>
+
+typedef uint64_t Key;
+typedef uint64_t Bitboard;
+
+const int PLY_MAX = 100;
+const int PLY_MAX_PLUS_2 = PLY_MAX + 2;
+
+enum ValueType {
+ VALUE_TYPE_NONE = 0,
+ VALUE_TYPE_UPPER = 1,
+ VALUE_TYPE_LOWER = 2,
+ VALUE_TYPE_EXACT = VALUE_TYPE_UPPER | VALUE_TYPE_LOWER
+};
+
+enum Value {
+ VALUE_ZERO = 0,
+ VALUE_DRAW = 0,
+ VALUE_KNOWN_WIN = 15000,
+ VALUE_MATE = 30000,
+ VALUE_INFINITE = 30001,
+ VALUE_NONE = 30002,
+
+ VALUE_MATE_IN_PLY_MAX = VALUE_MATE - PLY_MAX,
+ VALUE_MATED_IN_PLY_MAX = -VALUE_MATE + PLY_MAX,
+
+ VALUE_ENSURE_INTEGER_SIZE_P = INT_MAX,
+ VALUE_ENSURE_INTEGER_SIZE_N = INT_MIN
+};
+
+enum PieceType {
+ PIECE_TYPE_NONE = 0,
+ PAWN = 1, KNIGHT = 2, BISHOP = 3, ROOK = 4, QUEEN = 5, KING = 6
+};
+
+enum Piece {
+ PIECE_NONE_DARK_SQ = 0, WP = 1, WN = 2, WB = 3, WR = 4, WQ = 5, WK = 6,
+ BP = 9, BN = 10, BB = 11, BR = 12, BQ = 13, BK = 14, PIECE_NONE = 16
+};
+
+enum Color {
+ WHITE, BLACK, COLOR_NONE
+};
+
+enum Depth {
+
+ ONE_PLY = 2,
+
+ DEPTH_ZERO = 0 * ONE_PLY,
+ DEPTH_QS_CHECKS = -1 * ONE_PLY,
+ DEPTH_QS_NO_CHECKS = -2 * ONE_PLY,
+ DEPTH_QS_RECAPTURES = -4 * ONE_PLY,
+
+ DEPTH_NONE = -127 * ONE_PLY
+};
+
+enum Square {
+ 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,
+ SQ_A3, SQ_B3, SQ_C3, SQ_D3, SQ_E3, SQ_F3, SQ_G3, SQ_H3,
+ SQ_A4, SQ_B4, SQ_C4, SQ_D4, SQ_E4, SQ_F4, SQ_G4, SQ_H4,
+ SQ_A5, SQ_B5, SQ_C5, SQ_D5, SQ_E5, SQ_F5, SQ_G5, SQ_H5,
+ SQ_A6, SQ_B6, SQ_C6, SQ_D6, SQ_E6, SQ_F6, SQ_G6, SQ_H6,
+ SQ_A7, SQ_B7, SQ_C7, SQ_D7, SQ_E7, SQ_F7, SQ_G7, SQ_H7,
+ SQ_A8, SQ_B8, SQ_C8, SQ_D8, SQ_E8, SQ_F8, SQ_G8, SQ_H8,
+ SQ_NONE,
+
+ DELTA_N = 8,
+ DELTA_E = 1,
+ DELTA_S = -8,
+ DELTA_W = -1,
+
+ DELTA_NN = DELTA_N + DELTA_N,
+ DELTA_NE = DELTA_N + DELTA_E,
+ DELTA_SE = DELTA_S + DELTA_E,
+ DELTA_SS = DELTA_S + DELTA_S,
+ DELTA_SW = DELTA_S + DELTA_W,
+ DELTA_NW = DELTA_N + DELTA_W
+};
+
+enum File {
+ FILE_A, FILE_B, FILE_C, FILE_D, FILE_E, FILE_F, FILE_G, FILE_H
+};
+
+enum Rank {
+ RANK_1, RANK_2, RANK_3, RANK_4, RANK_5, RANK_6, RANK_7, RANK_8
+};
+
+enum SquareColor {
+ DARK, LIGHT
+};
+
+enum ScaleFactor {
+ SCALE_FACTOR_ZERO = 0,
+ SCALE_FACTOR_NORMAL = 64,
+ SCALE_FACTOR_MAX = 128,
+ SCALE_FACTOR_NONE = 255
+};
+
+
+/// Score enum keeps a midgame and an endgame value in a single
+/// integer (enum), first LSB 16 bits are used to store endgame
+/// value, while upper bits are used for midgame value. Compiler
+/// is free to choose the enum type as long as can keep its data,
+/// so ensure Score to be an integer type.
+enum Score {
+ SCORE_ZERO = 0,
+ SCORE_ENSURE_INTEGER_SIZE_P = INT_MAX,
+ SCORE_ENSURE_INTEGER_SIZE_N = INT_MIN
+};
+
+#define ENABLE_OPERATORS_ON(T) \
+inline T operator+ (const T d1, const T d2) { return T(int(d1) + int(d2)); } \
+inline T operator- (const T d1, const T d2) { return T(int(d1) - int(d2)); } \
+inline T operator* (int i, const T d) { return T(i * int(d)); } \
+inline T operator* (const T d, int i) { return T(int(d) * i); } \
+inline T operator/ (const T d, int i) { return T(int(d) / i); } \
+inline T operator- (const T d) { return T(-int(d)); } \
+inline T operator++ (T& d, int) {d = T(int(d) + 1); return d; } \
+inline T operator-- (T& d, int) { d = T(int(d) - 1); return d; } \
+inline void operator+= (T& d1, const T d2) { d1 = d1 + d2; } \
+inline void operator-= (T& d1, const T d2) { d1 = d1 - d2; } \
+inline void operator*= (T& d, int i) { d = T(int(d) * i); } \
+inline void operator/= (T& d, int i) { d = T(int(d) / i); }
+
+ENABLE_OPERATORS_ON(Value)
+ENABLE_OPERATORS_ON(PieceType)
+ENABLE_OPERATORS_ON(Piece)
+ENABLE_OPERATORS_ON(Color)
+ENABLE_OPERATORS_ON(Depth)
+ENABLE_OPERATORS_ON(Square)
+ENABLE_OPERATORS_ON(File)
+ENABLE_OPERATORS_ON(Rank)
+
+#undef ENABLE_OPERATORS_ON
+
+// Extra operators for adding integers to a Value
+inline Value operator+ (Value v, int i) { return Value(int(v) + i); }
+inline Value operator- (Value v, int i) { return Value(int(v) - i); }
+
+// Extracting the _signed_ lower and upper 16 bits it not so trivial
+// because according to the standard a simple cast to short is
+// implementation defined and so is a right shift of a signed integer.
+inline Value mg_value(Score s) { return Value(((s + 32768) & ~0xffff) / 0x10000); }
+
+// Unfortunatly on Intel 64 bit we have a small speed regression, so use a faster code in
+// this case, although not 100% standard compliant it seems to work for Intel and MSVC.
+#if defined(IS_64BIT) && (!defined(__GNUC__) || defined(__INTEL_COMPILER))
+inline Value eg_value(Score s) { return Value(int16_t(s & 0xffff)); }
+#else
+inline Value eg_value(Score s) { return Value((int)(unsigned(s) & 0x7fffu) - (int)(unsigned(s) & 0x8000u)); }
+#endif
+
+inline Score make_score(int mg, int eg) { return Score((mg << 16) + eg); }
+
+// Division must be handled separately for each term
+inline Score operator/(Score s, int i) { return make_score(mg_value(s) / i, eg_value(s) / i); }
+
+// 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.
+inline Score operator*(Score s1, Score s2);
+
+// Remaining Score operators are standard
+inline Score operator+ (const Score d1, const Score d2) { return Score(int(d1) + int(d2)); }
+inline Score operator- (const Score d1, const Score d2) { return Score(int(d1) - int(d2)); }
+inline Score operator* (int i, const Score d) { return Score(i * int(d)); }
+inline Score operator* (const Score d, int i) { return Score(int(d) * i); }
+inline Score operator- (const Score d) { return Score(-int(d)); }
+inline void operator+= (Score& d1, const Score d2) { d1 = d1 + d2; }
+inline void operator-= (Score& d1, const Score d2) { d1 = d1 - d2; }
+inline void operator*= (Score& d, int i) { d = Score(int(d) * i); }
+inline void operator/= (Score& d, int i) { d = Score(int(d) / i); }
+
+const Value PawnValueMidgame = Value(0x0C6);
+const Value PawnValueEndgame = Value(0x102);
+const Value KnightValueMidgame = Value(0x331);
+const Value KnightValueEndgame = Value(0x34E);
+const Value BishopValueMidgame = Value(0x344);
+const Value BishopValueEndgame = Value(0x359);
+const Value RookValueMidgame = Value(0x4F6);
+const Value RookValueEndgame = Value(0x4FE);
+const Value QueenValueMidgame = Value(0x9D9);
+const Value QueenValueEndgame = Value(0x9FE);
+
+extern const Value PieceValueMidgame[17];
+extern const Value PieceValueEndgame[17];
+
+inline Value piece_value_midgame(Piece p) {
+ return PieceValueMidgame[p];
+}
+
+inline Value piece_value_endgame(Piece p) {
+ return PieceValueEndgame[p];
+}
+
+inline Value value_mate_in(int ply) {
+ return VALUE_MATE - ply;
+}
+
+inline Value value_mated_in(int ply) {
+ return -VALUE_MATE + ply;
+}
+
+inline Piece make_piece(Color c, PieceType pt) {
+ return Piece((c << 3) | pt);
+}
+
+inline PieceType type_of_piece(Piece p) {
+ return PieceType(p & 7);
+}
+
+inline Color color_of_piece(Piece p) {
+ return Color(p >> 3);
+}
+
+inline Color opposite_color(Color c) {
+ return Color(c ^ 1);
+}
+
+inline char piece_type_to_char(PieceType pt) {
+ static const char ch[] = " PNBRQK";
+ return ch[pt];
+}
+
+inline Square make_square(File f, Rank r) {
+ return Square((r << 3) | f);
+}
+
+inline bool square_is_ok(Square s) {
+ return s >= SQ_A1 && s <= SQ_H8;
+}
+
+inline File square_file(Square s) {
+ return File(s & 7);
+}
+
+inline Rank square_rank(Square s) {
+ return Rank(s >> 3);
+}
+
+inline Square flip_square(Square s) {
+ return Square(s ^ 56);
+}
+
+inline Square flop_square(Square s) {
+ return Square(s ^ 7);
+}
+
+inline Square relative_square(Color c, Square s) {
+ return Square(s ^ (c * 56));
+}
+
+inline Rank relative_rank(Color c, Rank r) {
+ return Rank(r ^ (c * 7));
+}
+
+inline Rank relative_rank(Color c, Square s) {
+ return relative_rank(c, square_rank(s));
+}
+
+inline SquareColor square_color(Square s) {
+ return SquareColor(int(square_rank(s) + s) & 1);
+}
+
+inline bool opposite_color_squares(Square s1, Square s2) {
+ int s = s1 ^ s2;
+ return ((s >> 3) ^ s) & 1;
+}
+
+inline int file_distance(Square s1, Square s2) {
+ return abs(square_file(s1) - square_file(s2));
+}
+
+inline int rank_distance(Square s1, Square s2) {
+ return abs(square_rank(s1) - square_rank(s2));
+}
+
+inline int square_distance(Square s1, Square s2) {
+ return Max(file_distance(s1, s2), rank_distance(s1, s2));
+}
+
+inline char file_to_char(File f) {
+ return char(f - FILE_A + int('a'));
+}
+
+inline char rank_to_char(Rank r) {
+ return char(r - RANK_1 + int('1'));
+}
+
+inline const std::string square_to_string(Square s) {
+ char ch[] = { file_to_char(square_file(s)), rank_to_char(square_rank(s)), 0 };
+ return std::string(ch);
+}
+
+inline Square pawn_push(Color c) {
+ return c == WHITE ? DELTA_N : DELTA_S;
+}
+