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 = VALUE_TYPE_UPPER | VALUE_TYPE_LOWER
46 VALUE_KNOWN_WIN = 15000,
48 VALUE_INFINITE = 30001,
50 VALUE_ENSURE_SIGNED = -1
53 ENABLE_OPERATORS_ON(Value);
57 SCALE_FACTOR_ZERO = 0,
58 SCALE_FACTOR_NORMAL = 64,
59 SCALE_FACTOR_MAX = 128,
60 SCALE_FACTOR_NONE = 255
64 /// Score enum keeps a midgame and an endgame value in a single
65 /// integer (enum), first LSB 16 bits are used to store endgame
66 /// value, while upper bits are used for midgame value.
68 // Compiler is free to choose the enum type as long as can keep
69 // its data, so ensure Score to be an integer type.
72 SCORE_ENSURE_32_BITS_SIZE_P = (1 << 16),
73 SCORE_ENSURE_32_BITS_SIZE_N = -(1 << 16)
76 ENABLE_OPERATORS_ON(Score);
79 // Extracting the _signed_ lower and upper 16 bits it not so trivial
80 // because according to the standard a simple cast to short is
81 // implementation defined and so is a right shift of a signed integer.
82 inline Value mg_value(Score s) { return Value(((int(s) + 32768) & ~0xffff) / 0x10000); }
84 // Unfortunatly on Intel 64 bit we have a small speed regression, so use a faster code in
85 // this case, although not 100% standard compliant it seems to work for Intel and MSVC.
86 #if defined(IS_64BIT) && (!defined(__GNUC__) || defined(__INTEL_COMPILER))
87 inline Value eg_value(Score s) { return Value(int16_t(s & 0xffff)); }
89 inline Value eg_value(Score s) { return Value((int)(unsigned(s) & 0x7fffu) - (int)(unsigned(s) & 0x8000u)); }
92 inline Score make_score(int mg, int eg) { return Score((mg << 16) + eg); }
94 // Division must be handled separately for each term
95 inline Score operator/(Score s, int i) { return make_score(mg_value(s) / i, eg_value(s) / i); }
97 // Only declared but not defined. We don't want to multiply two scores due to
98 // a very high risk of overflow. So user should explicitly convert to integer.
99 inline Score operator*(Score s1, Score s2);
103 //// Inline functions
106 inline Value operator+ (Value v, int i) { return Value(int(v) + i); }
107 inline Value operator- (Value v, int i) { return Value(int(v) - i); }
110 inline Value value_mate_in(int ply) {
111 return VALUE_MATE - ply;
114 inline Value value_mated_in(int ply) {
115 return -VALUE_MATE + ply;
118 #endif // !defined(VALUE_H_INCLUDED)