It isn't generally expensive at all. Most compilers and processors can work with 64-bit numbers inherently.
However, different compilers do use different terms for explicit 64-bit terminology. In MS C++ the internal type name is '__int64', as all of their integer types are actually aliases for __intXX precision-defining monikers (char is __int8, short is __int16, WORD would be 'unsigned __int16', etc.)
LONGLONG (all caps) is a common typedef defined in Windows.h for MS C++ as well, which maps to __int64.
|