Which is better option to use for dividing an integer number by 2?
Use the operation that best describes what you are trying to do.
- If you are treating the number as a sequence of bits, use bitshift.
- If you are treating it as a numerical value, use division.
Note that they are not exactly equivalent. They can give different results for negative integers. For example:
-5 / 2 = -2
-5 >> 1 = -3
(ideone)
Does the first one look like dividing? No. If you want to divide, use x / 2. Compiler can optimise it to use bit-shift if possible (it's called strength reduction), which makes it a useless micro-optimisation if you do it on your own.