I have a source code of a library which has a lot of strange IF, ELSE, FOR, etc. macros for all common C-keywords instead of using just usual if,else,for,while keywords. These macros are defined like this:

 #define IF( a) if( increment_if(), a)

where increment_if() function is defined so:

static __inline void increment_if( void) {
    // If the "IF" operator comes just after an "ELSE", its counter
    // must not be incremented.
    ... //implementation
}

I don't really understand, what is the purpose of such macros? This library is for a real-time application and I suppose that using such macros must slow-down an application.