1.4.3 (Bitwise manipulation)

Question 1

What is bitwise manipulation?

Answer 1

• Moving binary numbers left or right to multiply or divide

Question 2

What is a bitwise shift?

Answer 2

• Multiplies or divides a binary number by moving digits right or left

Question 3

What is a logical shift?

Answer 3

• Moves all bits to the right or left
• Fills the gaps with 0s

Question 4

What is an arithmetic shift?

Answer 4

• Shifts bits while maintaining the sign bit

Question 5

What are the rules for an arithmetic shift?

Answer 5

• If dividing: if the MSB is 1, feed 1’s into the gap after the MSB. if the MSB is 0, feed 0’s into the gap
• If multiplying: feed in 0’s

Question 6

What is a circular shift?

Answer 6

• A shift that moves a bit into the carry bit at one end and takes a bit out at the other end

Question 7

What are the rules for a circular shift?

Answer 7

• If dividing: the LSB goes into the MSB
• If multiplying: the MSB goes into the LSB

Question 8

What does an AND mask do to the bits?

Answer 8

• 0’s set to 0
• 1’s keep the original bit

Question 9

What does an OR mask do to the bits?

Answer 9

• 1’s set to 1
• 0’s keep the original bit

Question 10

What does a XOR mask do to the bits?

Answer 10

• 0’s keep the original bit
• 1’s NOT the original bit (Flip the bit)