No amount of bit-bashing can fix really poor choices of algorithms (N^2 vs NlogN, say, on a big input).
Its also worth noting that sometimes an algorithm with higher O() complexity could actually perform better. Eg, a brute-force linear search may be faster than a binary search if the elements can be efficiently cache prefetched, or if the entire dataset fits into cache.
Its also worth noting that sometimes an algorithm with higher O() complexity could actually perform better. Eg, a brute-force linear search may be faster than a binary search if the elements can be efficiently cache prefetched, or if the entire dataset fits into cache.