Question

I got a question regarding shifting bits within an unsigned integer. I’ve got two unsigned integers, let’s say var1 and var2. I need to take the left most var1 bits of var2 and move them to the right most position. So if var1 is 12 and var2 is 0x13ac8d08 that would result in var2 becoming 0xc8d0813a. Can anyone help me how to do that in C#?

thanks

Michael

Answer 1

Try this:

var2 = (var2 << var1) | (var2 >> (32 - var1));

In method form:

uint CyclicShiftLeft(uint input,int countBits)
{
   return (input << countBits) | (input >> (32 - countBits))
}

Edit

Please see the comments for the significance of the 32 in the above code.