Variable x is int with possible values: -1, 0, 1, 2, 3. Which expression will be faster (in CPU ticks):
x
-1, 0, 1, 2, 3
1. (x < 0) 2. (x == -1)
x < 0 will be faster. If nothing else, it prevents fetching the constant -1 as an operand. Most architectures have special instructions for comparing against zero, so that will help too.