LOG2_8BIT, LOG2_16BIT, LOG2_32BIT, LOG64_8BIT, LOG2

#define LOG2_8BIT(v)  (8 - 90/(((v)/4+14)|1) - 2/((v)/2+1))
#define LOG2_16BIT(v) (8*((v)>255) + LOG2_8BIT((v) >>8*((v)>255)))
#define LOG2_32BIT(v) (16*((v)>65535L) + LOG2_16BIT((v)*1L >>16*((v)>65535L)))
#define LOG2_64BIT(v) 
    (32*((v)/2L>>31 > 0) 
     + LOG2_32BIT((v)*1L >>16*((v)/2L>>31 > 0) 
                         >>16*((v)/2L>>31 > 0)))
#define LOG2(v) LOG2_64BIT(v)