C quick calculation of next multiple of 4?

Question

What\'s a fast way to round up an unsigned int to a multiple of 4?

A multiple of 4 has the two least significant bits 0, right? So I could

Answer 1

If you want the next multiple of 4 strictly greater than myint, this solution will do (similar to previous posts):

(myint + 4) & ~3u

If you instead want to round up to the nearest multiple of 4 (leaving myint unchanged if it is a multiple of 4), this should work:

(0 == myint & 0x3) ? myint : ((myint + 4) & ~3u);