X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fvalue.h;h=4b62027267847592c63ef4a50895dc5b292625e4;hp=c86430c6a06e056192ee39a7c1a0ff08887ff138;hb=06a350f1aee97f05c3416853fb54385b23030ebc;hpb=dda7e4639aa19b91f2bafd2e8fb5b55c57eda97a diff --git a/src/value.h b/src/value.h index c86430c6..4b620272 100644 --- a/src/value.h +++ b/src/value.h @@ -1,7 +1,7 @@ /* Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) - Copyright (C) 2008-2009 Marco Costalba + Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, 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 @@ -33,13 +33,16 @@ //// enum ValueType { - VALUE_TYPE_NONE = 0, + VALUE_TYPE_NONE = 0, VALUE_TYPE_UPPER = 1, // Upper bound VALUE_TYPE_LOWER = 2, // Lower bound VALUE_TYPE_EXACT = 3, // Exact score - VALUE_TYPE_EVAL = 4, // Evaluation cache - VALUE_TYPE_EV_UP = 5, // Evaluation cache for upper bound - VALUE_TYPE_EV_LO = 6 // Evaluation cache for lower bound + VALUE_TYPE_EVAL = 4, // Static evaluation value + VALUE_TYPE_NULL = 8, // Null search value + + VALUE_TYPE_EV_UP = VALUE_TYPE_EVAL | VALUE_TYPE_UPPER, + VALUE_TYPE_EV_LO = VALUE_TYPE_EVAL | VALUE_TYPE_LOWER, + VALUE_TYPE_NS_LO = VALUE_TYPE_NULL | VALUE_TYPE_LOWER, }; @@ -48,48 +51,48 @@ enum Value { VALUE_KNOWN_WIN = 15000, VALUE_MATE = 30000, VALUE_INFINITE = 30001, - VALUE_NONE = 30002 + VALUE_NONE = 30002, + VALUE_ENSURE_SIGNED = -1 }; -/// Score struct keeps a midgame and an endgame value in a single -/// ScoreValue 64 bit union. - -union ScoreValue { - int64_t v64; - struct { - int32_t mgv; - int32_t egv; - } v32; -}; +/// 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. -struct Score { +// 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 { ENSURE_32_BITS_SIZE_P = (1 << 16), ENSURE_32_BITS_SIZE_N = -(1 << 16)}; - Score() {} - Score(const Score& s) { v = s.v; } - Score(int mg, int eg) { v.v32.mgv = int32_t(mg); v.v32.egv = int32_t(eg); } +// 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(((int(s) + 32768) & ~0xffff) / 0x10000); } - Score& operator=(const Score& s) { v = s.v; return *this; } - Score& operator+=(const Score& s) { v.v32.mgv += s.v.v32.mgv; v.v32.egv += s.v.v32.egv; return *this; } - Score& operator-=(const Score& s) { v.v32.mgv -= s.v.v32.mgv; v.v32.egv -= s.v.v32.egv; return *this; } +// 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 - bool operator==(const Score& s) { return v.v64 == s.v.v64; } - bool operator!=(const Score& s) { return v.v64 != s.v.v64; } +inline Score make_score(int mg, int eg) { return Score((mg << 16) + eg); } - Value mg() const { return Value(v.v32.mgv); } - Value eg() const { return Value(v.v32.egv); } +inline Score operator-(Score s) { return Score(-int(s)); } +inline Score operator+(Score s1, Score s2) { return Score(int(s1) + int(s2)); } +inline Score operator-(Score s1, Score s2) { return Score(int(s1) - int(s2)); } +inline void operator+=(Score& s1, Score s2) { s1 = Score(int(s1) + int(s2)); } +inline void operator-=(Score& s1, Score s2) { s1 = Score(int(s1) - int(s2)); } +inline Score operator*(int i, Score s) { return Score(i * int(s)); } -private: - ScoreValue v; -}; +// 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); } -inline Score operator-(Score s1, Score s2) { return Score(s1.mg() - s2.mg(), s1.eg() - s2.eg()); } -inline Score operator*(int i, Score s) { return Score(i * s.mg(), i * s.eg()); } -inline Score operator*(Score s, int i) { return s * i; } -inline Score operator/(Score s, int i) { return Score(s.mg() / i, s.eg() / i); } -inline Score operator-(Score s) { return Score(-s.mg(), -s.eg()); } +// 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); -extern std::ostream& operator<<(std::ostream& os, Score s); //// //// Constants and variables @@ -136,7 +139,7 @@ const Value PieceValueEndgame[17] = { /// Bonus for having the side to move (modified by Joona Kiiski) -const Score TempoValue = Score(48, 22); +const Score TempoValue = make_score(48, 22); ////