madeeasy test

Question

is it right to pre assume that operand will be forwarded from WB stage to EX(even though it is not mentioned)??

Answer 1

Nope. Here operand is being Forwarded From  MA to EX stage .  Not WB to EX as you have mentioned in the image .
Operand Forwarding stage will depend on type of instruction .  Here I2 isMemory Related Instruction

Here is the complete Solution of the above question .

Here is the general Senario of Operand Forwarding Probably this woulod give a general idea.

This is also a good question to practise

However this was also happened in GATE 2015. " When to use split phase "  without mentioning explicitly in question is still not resolved .

Comments

(without forwarding=18 cycle)
IF ID EX MA WB
    IF  ID  EX  MA WB
         IF    -     -     -     ID EX MA WB
                                   IF  -     -      -   ID EX MA WB
                                                          IF  -     -      -    ID EX MA WB
--------------------------------------------------------------------------------------------
(Forwarding=12 cycle)
IF ID EX MA WB
    IF ID EX MA WB
        IF   -    ID   EX MA WB
                    IF   -     ID EX MA WB     so ans 18-12
@pc plz check this

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Answer Updated ..!

@jeny_singh
see all the links in the answer. It should be clear . This is already answered .
In your without operand forwarding case . ID and WB can execute in same clock cycle . Just see this GATE 2005 Question

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thank u @pc, i got the point