Quiz submission record for quiz6-1-1 at Mon Jul 26 10:45:11 2004:

Your Answer for Question 1:
The excution, memory access and writing back to register stages of the control flow will not be able to catch up with the use of new instructions acting on different reigsters than the first instruction.

Your Answer for Question 2:
One is from the register file, another is from the prior ALU result and finally data memory or an earlier ALU result can be forwarded.

add $1, $1, $2
add $1, $1, $3 
will make use the forward from the prior ALU result

lw $1,0($2)
add $4, $5, $7
add $2,$3,$1 
will make use the forward from register

lw $1,0($2)
add $2, $3, $1
will make use of the forward from data memory



Your Answer for Question 3:
It stops the a stage that is stalling by preventing the change it the instructions and also repeats of a stage of instruction in subsequent instructions. 

The forwarding control unit will eventually stop the stall.


Your unique submission ID is quiz6-1-1-cs61c-ba-1090863911-2590.