X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fvalue.h;h=d86a8bb90017126a02acbae20211107fc3a501ab;hp=269102412cb8250ea83dac2c60457eb6c6526ece;hb=a5ae7fe26030bdd73a95fde3ebe841abfe84ec5e;hpb=15ec3e911e231bd992c2e3cf3f7785db6e29f20b

diff --git a/src/value.h b/src/value.h
index 26910241..d86a8bb9 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
@@ -33,65 +33,70 @@
 ////
 
 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_EXACT = VALUE_TYPE_UPPER | VALUE_TYPE_LOWER
 };
 
 
 enum Value {
-  VALUE_DRAW = 0,
+  VALUE_ZERO      = 0,
+  VALUE_DRAW      = 0,
   VALUE_KNOWN_WIN = 15000,
-  VALUE_MATE = 30000,
-  VALUE_INFINITE = 30001,
-  VALUE_NONE = 30002
+  VALUE_MATE      = 30000,
+  VALUE_INFINITE  = 30001,
+  VALUE_NONE      = 30002,
+  VALUE_ENSURE_SIGNED = -1
 };
 
+ENABLE_OPERATORS_ON(Value);
 
-/// 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;
+enum ScaleFactor {
+  SCALE_FACTOR_ZERO   = 0,
+  SCALE_FACTOR_NORMAL = 64,
+  SCALE_FACTOR_MAX    = 128,
+  SCALE_FACTOR_NONE   = 255
 };
 
-struct Score {
 
-    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); }
+/// 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.
 
-    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; }
+// 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)
+};
 
-    bool operator==(const Score& s) { return v.v64 == s.v.v64; }
-    bool operator!=(const Score& s) { return v.v64 != s.v.v64; }
+ENABLE_OPERATORS_ON(Score);
 
-    Value mg() const { return Value(v.v32.mgv); }
-    Value eg() const { return Value(v.v32.egv); }
 
-private:
-    ScoreValue v;
-};
+// 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); }
+
+// 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); }
 
-inline Score operator+(Score s1, Score s2) { return Score(s1.mg() + s2.mg(), s1.eg() + s2.eg()); }
-inline Score operator-(Score s1, Score s2) { return Score(s1.mg() - s2.mg(), s1.eg() - s2.eg()); }
-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 Score(s.mg() * i, s.eg() * 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()); }
+// 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);
 
-extern std::ostream& operator<<(std::ostream& os, Score s);
 
 ////
 //// Constants and variables
@@ -117,28 +122,28 @@ const Value QueenValueMidgame  = Value(0x9D9);
 const Value QueenValueEndgame  = Value(0x9FE);
 
 const Value PieceValueMidgame[17] = {
-  Value(0),
+  VALUE_ZERO,
   PawnValueMidgame, KnightValueMidgame, BishopValueMidgame,
   RookValueMidgame, QueenValueMidgame,
-  Value(0), Value(0), Value(0),
+  VALUE_ZERO, VALUE_ZERO, VALUE_ZERO,
   PawnValueMidgame, KnightValueMidgame, BishopValueMidgame,
   RookValueMidgame, QueenValueMidgame,
-  Value(0), Value(0), Value(0)
+  VALUE_ZERO, VALUE_ZERO, VALUE_ZERO
 };
 
 const Value PieceValueEndgame[17] = {
-  Value(0),
+  VALUE_ZERO,
   PawnValueEndgame, KnightValueEndgame, BishopValueEndgame,
   RookValueEndgame, QueenValueEndgame,
-  Value(0), Value(0), Value(0),
+  VALUE_ZERO, VALUE_ZERO, VALUE_ZERO,
   PawnValueEndgame, KnightValueEndgame, BishopValueEndgame,
   RookValueEndgame, QueenValueEndgame,
-  Value(0), Value(0), Value(0)
+  VALUE_ZERO, VALUE_ZERO, VALUE_ZERO
 };
 
 /// Bonus for having the side to move (modified by Joona Kiiski)
 
-const Score TempoValue = Score(48, 22);
+const Score TempoValue = make_score(48, 22);
 
 
 ////
@@ -146,29 +151,15 @@ const Score TempoValue = Score(48, 22);
 ////
 
 inline Value operator+ (Value v, int i) { return Value(int(v) + i); }
-inline Value operator+ (Value v1, Value v2) { return Value(int(v1) + int(v2)); }
-inline void operator+= (Value &v1, Value v2) {
-  v1 = Value(int(v1) + int(v2));
-}
 inline Value operator- (Value v, int i) { return Value(int(v) - i); }
-inline Value operator- (Value v) { return Value(-int(v)); }
-inline Value operator- (Value v1, Value v2) { return Value(int(v1) - int(v2)); }
-inline void operator-= (Value &v1, Value v2) {
-  v1 = Value(int(v1) - int(v2));
-}
-inline Value operator* (Value v, int i) { return Value(int(v) * i); }
-inline void operator*= (Value &v, int i) { v = Value(int(v) * i); }
-inline Value operator* (int i, Value v) { return Value(int(v) * i); }
-inline Value operator/ (Value v, int i) { return Value(int(v) / i); }
-inline void operator/= (Value &v, int i) { v = Value(int(v) / i); }
 
 
 inline Value value_mate_in(int ply) {
-  return Value(VALUE_MATE - Value(ply));
+  return VALUE_MATE - ply;
 }
 
 inline Value value_mated_in(int ply) {
-  return Value(-VALUE_MATE + Value(ply));
+  return -VALUE_MATE + ply;
 }
 
 inline bool is_upper_bound(ValueType vt) {
@@ -195,16 +186,4 @@ inline Value piece_value_endgame(Piece p) {
   return PieceValueEndgame[p];
 }
 
-
-////
-//// Prototypes
-////
-
-extern Value value_to_tt(Value v, int ply);
-extern Value value_from_tt(Value v, int ply);
-extern int value_to_centipawns(Value v);
-extern Value value_from_centipawns(int cp);
-extern const std::string value_to_string(Value v);
-
-
 #endif // !defined(VALUE_H_INCLUDED)