1. Data Hazard Example
(no stalls)

2. Code sub $2, $1, $3 add $4, $2, $5 add $4, $4, $2 add $9, $2, $4 Where
contents of $1 is initially 30
contents of $2 is initially 57
contents of $3 is initially 8
contents of $4 is initially 61
contests of $5 is initially 24

3. sub $2, $1, $3

4. add $4, $2, $5
sub $2, $1, $3 30 1 3 8 1 3 3 2

5. add $4, $4, $2
add $4, $2, $5
sub $2, $1, $3 57 30 2 30 5 22 24 8 8 2 5 5 3 2 4 2 1 3

6. Forwarding unit compares these registers
add $9, $2, $4
add $4, $4, $2
add $4, $2, $5
sub $2, $1, $3
Forwarding unit compares these registers 61 57 4 22 2 22 10 46 57 24 24 4 22 2 2 5 4 2 4 4 2 2 1 5

7. add $9, $2, $4 add $4, $4, $2 add $4, $2, $5 sub $2, $1, $3 61 2 57 2246 4 46 2 10 68 22 61 57 22 22 22 22 01 2 46 4 4 2 4 4 9 4 4 4 1 2 2 1

8. add $9, $2, $4
add $4, $4, $2
add $4,
$2, $5 22 22 4 90 46 61 46 46 68 46 68 10 68 4 9 4 9 4 2 1 4 4 1