Section 6.7
Review Questions

Shifts

  1. Match the kind of shift to a description of it or some clue that identifies it:
          logical shift                     no new bits are inserted
          
          
          circular shift                    the sign bit is stuck
          
          
          arithmetic shift                  some bits get lost or destroyed
  1. What is another name for circular shift?
  1. Which of the following actually does division by 2? Circle all that might apply:
     left logical             left arithmetic            left circular
     
     right logical            right arithmetic           right circular
  1. Which of the following actually does multiplication by 2? Circle all that might apply:
     left logical             left arithmetic            left circular
     
     right logical            right arithmetic           right circular
  1. Perform all the following shifts on the bit pattern 10100001:
               1-bit left logical          ______________________________
               
               1-bit right logical         ______________________________
               
               1-bit left circular         ______________________________
               
               1-bit right circular        ______________________________
               
               1-bit left arithmetic       ______________________________
               
               1-bit right arithmetic      ______________________________
  1. What would happen to the sign of a negative number if you performed a right logical shift on the number? (The number could be either 2's complement or sign-magnitude.)