};
-/// Score struct keeps a midgame and an endgame value in a single
-/// ScoreValue 64 bit union.
+/// 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.
-enum Score;
+enum Score {};
inline Value eg_value(Score s) { return Value(int16_t(s & 0xffff)); }
inline Value mg_value(Score s) { return Value((int(s) + 32768) >> 16); }
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)); }
-inline Score operator/(Score s, int i) { return Score(int(s) / i); }
+
+// 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);
-// Following are only declared to prevent erroneus instantations
-inline Score operator*(Score s, int i);
-inline Score operator/(Score s1, Score s2);
-inline Score operator+(Score s, int i);
-inline Score operator+(int i, Score s);
-inline Score operator-(Score s, int i);
-inline Score operator-(int i, Score s);
-
////
//// Constants and variables