Please see the Instruction on how to post legible code:
http://www.8052.com/forum/read.phtml?id=127942


As Jez says, this is nothing specifically to do with SDCC.

You already have arithmetic in your preprocessor defines:

#define XTAL 22118400
#define MACHINE_CYCLE 12
#define TMR_OV_SEC XTAL/MACHINE_CYCLE
#define F40TH_OF_SECOND TMR_OV_SEC * 0.025   
#define TIME_SCND 40
#define CLOCK_RELOAD 65536-F40TH_OF_SECOND+14

Not that the preprocessor does not actually do any of this arithmetic - it just substitutes the text.

This is where it becomes compiler-specific: most compilers will evaluate constant expressions at compile-time - you need to check the SDCC Manual to confirm this, and whether it's considered an "optimisation" that needs to be enabled...

So, just make #defines that do the necessary shift-and-mask operations to extract the high & low bytes...