X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Ftypes.h;h=f6d993d07cf56be595331b9ce3ed5f892559a63b;hp=0c12d930490bb6c4516c817fe2950d67f4c45ec7;hb=85a7456bd7e8a1a01cdbfa8f4b6fb563d15a37c6;hpb=85559cc5972f93a2e7618d29b4b2cdcb79c55f98

diff --git a/src/types.h b/src/types.h
index 0c12d930..f6d993d0 100644
--- a/src/types.h
+++ b/src/types.h
@@ -109,4 +109,64 @@ inline void __cpuid(int CPUInfo[4], int)
 }
 #endif
 
+
+// Templetized operators used by enum types like Depth, Piece, Square and so on.
+// We don't want to write the same inline for each different enum. Note that we
+// pass by value to silence scaring warnings when using volatiles.
+// Because these templates override common operators and are included in all the
+// files, there is a possibility that the compiler silently performs some unwanted
+// overrides. To avoid possible very nasty bugs the templates are disabled by default
+// and must be enabled for each type on a case by case base. The enabling trick
+// uses template specialization, namely we just declare following struct.
+template<typename T> struct TempletizedOperator;
+
+// Then to enable the enum type we use following macro that defines a specialization
+// of TempletizedOperator for the given enum T. Here is defined typedef Not_Enabled.
+// Name of typedef is chosen to produce somewhat informative compile error messages.
+#define ENABLE_OPERATORS_ON(T)  \
+        template<> struct TempletizedOperator<T> { typedef T Not_Enabled; }
+
+// Finally we use macro OK(T) to check if type T is enabled. The macro simply
+// tries to use Not_Enabled, if was not previously defined a compile error occurs.
+// The check is done fully at compile time and there is zero overhead at runtime.
+#define OK(T) typedef typename TempletizedOperator<T>::Not_Enabled Type
+
+template<typename T>
+inline T operator+ (const T d1, const T d2) { OK(T); return T(int(d1) + int(d2)); }
+
+template<typename T>
+inline T operator- (const T d1, const T d2) { OK(T); return T(int(d1) - int(d2)); }
+
+template<typename T>
+inline T operator* (int i, const T d) { OK(T); return T(i * int(d)); }
+
+template<typename T>
+inline T operator* (const T d, int i) { OK(T); return T(int(d) * i); }
+
+template<typename T>
+inline T operator/ (const T d, int i) { OK(T); return T(int(d) / i); }
+
+template<typename T>
+inline T operator- (const T d) { OK(T); return T(-int(d)); }
+
+template<typename T>
+inline T operator++ (T& d, int) { OK(T); d = T(int(d) + 1); return d; }
+
+template<typename T>
+inline T operator-- (T& d, int) { OK(T); d = T(int(d) - 1); return d; }
+
+template<typename T>
+inline void operator+= (T& d1, const T d2) { OK(T); d1 = d1 + d2; }
+
+template<typename T>
+inline void operator-= (T& d1, const T d2) { OK(T); d1 = d1 - d2; }
+
+template<typename T>
+inline void operator*= (T& d, int i) { OK(T); d = T(int(d) * i); }
+
+template<typename T>
+inline void operator/= (T& d, int i) { OK(T); d = T(int(d) / i); }
+
+#undef OK
+
 #endif // !defined(TYPES_H_INCLUDED)