Hi,
I know about macro definition (I use them often and often in my C- and ASM- projects. I just cannot imagine how it can help me to reduce the program size: as I know, macro definitions are translated into real sequences at the first pass of a compiler and so any macro is not usable as modifiable value at program execution time. In short, macro is compiler feature; it has no sense at real code execution. Using macro you increase program size (compare with usage of subroutines) but take back some speed up.

Thank you and good days!