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SDCC Manual 8.1.12 Higher Order Byte / Higher Order Word It is also frequently required to obtain a higher order byte or word of a larger integral type (long, int or short types). SDCC recognizes the following expressions to yield the higher order byte or word and generates optimized code for it, e.g.: unsigned int gint;   unsigned long int glong;     foo () {     unsigned char hob1, hob2;     unsigned int how1, how2;     ...     hob1 = (gint >> 8) & 0xFF;     hob2 = glong >> 24;     how1 = (glong >> 16) & 0xFFFF;     how2 = glong >> 8;     ..   } will generate the following code:                           91 ;  hob.c 15   0037 85*01*06             92         mov   _foo_hob1_1_1,(_gint + 1)                             93 ;  hob.c 16   003A 85*05*07             94         mov   _foo_hob2_1_1,(_glong + 3)                             95 ;  hob.c 17   003D 85*04*08             96         mov   _foo_how1_1_1,(_glong + 2)   0040 85*05*09             97         mov   (_foo_how1_1_1 + 1),(_glong + 3)   0043 85*03*0A             98         mov   _foo_how2_1_1,(_glong + 1)   0046 85*04*0B             99         mov   (_foo_how2_1_1 + 1),(_glong + 2) Again, variations of these cases may not be recognized. They are standard C expressions, so I heartily recommend these be the only way to get the higher order byte/word, (it is portable). Of course it will be recognized even if it is embedded in other expressions, e.g.: xyz = gint + ((gint >> 8) & 0xFF); will still be recognized.