2 Stockfish, a UCI chess playing engine derived from Glaurung 2.1
3 Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
4 Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad
6 Stockfish is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation, either version 3 of the License, or
9 (at your option) any later version.
11 Stockfish is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>.
21 #if !defined(VALUE_H_INCLUDED)
22 #define VALUE_H_INCLUDED
37 VALUE_TYPE_UPPER = 1, // Upper bound
38 VALUE_TYPE_LOWER = 2, // Lower bound
39 VALUE_TYPE_EXACT = 3, // Exact score
40 VALUE_TYPE_EVAL = 4, // Static evaluation value
41 VALUE_TYPE_NULL = 8, // Null search value
43 VALUE_TYPE_EV_UP = VALUE_TYPE_EVAL | VALUE_TYPE_UPPER,
44 VALUE_TYPE_EV_LO = VALUE_TYPE_EVAL | VALUE_TYPE_LOWER,
45 VALUE_TYPE_NS_LO = VALUE_TYPE_NULL | VALUE_TYPE_LOWER,
51 VALUE_KNOWN_WIN = 15000,
53 VALUE_INFINITE = 30001,
55 VALUE_ENSURE_SIGNED = -1
59 /// Score enum keeps a midgame and an endgame value in a single
60 /// integer (enum), first LSB 16 bits are used to store endgame
61 /// value, while upper bits are used for midgame value.
63 // Compiler is free to choose the enum type as long as can keep
64 // its data, so ensure Score to be an integer type.
65 enum Score { ENSURE_32_BITS_SIZE_P = (1 << 16), ENSURE_32_BITS_SIZE_N = -(1 << 16)};
67 // Extracting the _signed_ lower and upper 16 bits it not so trivial
68 // because according to the standard a simple cast to short is
69 // implementation defined and so is a right shift of a signed integer.
70 inline Value mg_value(Score s) { return Value(((int(s) + 32768) & ~0xffff) / 0x10000); }
72 // Unfortunatly on Intel 64 bit we have a small speed regression, so use a faster code in
73 // this case, although not 100% standard compliant it seems to work for Intel and MSVC.
74 #if defined(IS_64BIT) && (!defined(__GNUC__) || defined(__INTEL_COMPILER))
75 inline Value eg_value(Score s) { return Value(int16_t(s & 0xffff)); }
77 inline Value eg_value(Score s) { return Value((int)(unsigned(s) & 0x7fffu) - (int)(unsigned(s) & 0x8000u)); }
80 inline Score make_score(int mg, int eg) { return Score((mg << 16) + eg); }
82 inline Score operator-(Score s) { return Score(-int(s)); }
83 inline Score operator+(Score s1, Score s2) { return Score(int(s1) + int(s2)); }
84 inline Score operator-(Score s1, Score s2) { return Score(int(s1) - int(s2)); }
85 inline void operator+=(Score& s1, Score s2) { s1 = Score(int(s1) + int(s2)); }
86 inline void operator-=(Score& s1, Score s2) { s1 = Score(int(s1) - int(s2)); }
87 inline Score operator*(int i, Score s) { return Score(i * int(s)); }
89 // Division must be handled separately for each term
90 inline Score operator/(Score s, int i) { return make_score(mg_value(s) / i, eg_value(s) / i); }
92 // Only declared but not defined. We don't want to multiply two scores due to
93 // a very high risk of overflow. So user should explicitly convert to integer.
94 inline Score operator*(Score s1, Score s2);
98 //// Constants and variables
101 /// Piece values, middle game and endgame
103 /// Important: If the material values are changed, one must also
104 /// adjust the piece square tables, and the method game_phase() in the
107 /// Values modified by Joona Kiiski
109 const Value PawnValueMidgame = Value(0x0C6);
110 const Value PawnValueEndgame = Value(0x102);
111 const Value KnightValueMidgame = Value(0x331);
112 const Value KnightValueEndgame = Value(0x34E);
113 const Value BishopValueMidgame = Value(0x344);
114 const Value BishopValueEndgame = Value(0x359);
115 const Value RookValueMidgame = Value(0x4F6);
116 const Value RookValueEndgame = Value(0x4FE);
117 const Value QueenValueMidgame = Value(0x9D9);
118 const Value QueenValueEndgame = Value(0x9FE);
120 const Value PieceValueMidgame[17] = {
122 PawnValueMidgame, KnightValueMidgame, BishopValueMidgame,
123 RookValueMidgame, QueenValueMidgame,
124 Value(0), Value(0), Value(0),
125 PawnValueMidgame, KnightValueMidgame, BishopValueMidgame,
126 RookValueMidgame, QueenValueMidgame,
127 Value(0), Value(0), Value(0)
130 const Value PieceValueEndgame[17] = {
132 PawnValueEndgame, KnightValueEndgame, BishopValueEndgame,
133 RookValueEndgame, QueenValueEndgame,
134 Value(0), Value(0), Value(0),
135 PawnValueEndgame, KnightValueEndgame, BishopValueEndgame,
136 RookValueEndgame, QueenValueEndgame,
137 Value(0), Value(0), Value(0)
140 /// Bonus for having the side to move (modified by Joona Kiiski)
142 const Score TempoValue = make_score(48, 22);
146 //// Inline functions
149 inline Value operator+ (Value v, int i) { return Value(int(v) + i); }
150 inline Value operator+ (Value v1, Value v2) { return Value(int(v1) + int(v2)); }
151 inline void operator+= (Value &v1, Value v2) {
152 v1 = Value(int(v1) + int(v2));
154 inline Value operator- (Value v, int i) { return Value(int(v) - i); }
155 inline Value operator- (Value v) { return Value(-int(v)); }
156 inline Value operator- (Value v1, Value v2) { return Value(int(v1) - int(v2)); }
157 inline void operator-= (Value &v1, Value v2) {
158 v1 = Value(int(v1) - int(v2));
160 inline Value operator* (Value v, int i) { return Value(int(v) * i); }
161 inline void operator*= (Value &v, int i) { v = Value(int(v) * i); }
162 inline Value operator* (int i, Value v) { return Value(int(v) * i); }
163 inline Value operator/ (Value v, int i) { return Value(int(v) / i); }
164 inline void operator/= (Value &v, int i) { v = Value(int(v) / i); }
167 inline Value value_mate_in(int ply) {
168 return Value(VALUE_MATE - Value(ply));
171 inline Value value_mated_in(int ply) {
172 return Value(-VALUE_MATE + Value(ply));
175 inline bool is_upper_bound(ValueType vt) {
176 return (int(vt) & int(VALUE_TYPE_UPPER)) != 0;
179 inline bool is_lower_bound(ValueType vt) {
180 return (int(vt) & int(VALUE_TYPE_LOWER)) != 0;
183 inline Value piece_value_midgame(PieceType pt) {
184 return PieceValueMidgame[pt];
187 inline Value piece_value_endgame(PieceType pt) {
188 return PieceValueEndgame[pt];
191 inline Value piece_value_midgame(Piece p) {
192 return PieceValueMidgame[p];
195 inline Value piece_value_endgame(Piece p) {
196 return PieceValueEndgame[p];
204 extern Value value_to_tt(Value v, int ply);
205 extern Value value_from_tt(Value v, int ply);
206 extern int value_to_centipawns(Value v);
207 extern Value value_from_centipawns(int cp);
208 extern const std::string value_to_string(Value v);
211 #endif // !defined(VALUE_H_INCLUDED)