Computational operations

When optimizing a specific algorithm for a specific microarchitecture the main question is: “How to perform the operations needed by the algorithm with the set operations available”. Microcontrollers often contain specialized circuitry for computationally hard tasks. It is recommended to go through the ways these can be used and check if any are usable by the algorithm. This is not always straightforward; sometimes part of a specialized operation can be used such as shown in Unsigned Accumulate Long, or a specialized instruction can be used in some other unintended way, as shown in SEL based conditional move.