Question

In Operand Forwarding technique how does the next instruction is able to access the dependent operand which is calculated in the previous instruction in the same Cpu Cycle?

Answer 1

In the same CPU cycle is not possible. Operand forwarding happens in the next cycle after the operation producing the operand is finished.

But there is a catch here:

If the operand forwarding happens from EX stage to EX stage, EX of the second instruction can proceed only in the next clock cycle.

Comments

How can we be sure result is obtained in first half? Suppose EX is for a multiply operation. Input needs to traverse through some gates and then only we get output. So, we can not assume this will be done in half a cycle.

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what about this question ?

https://gateoverflow.in/8218/gate2015-2_44

here is your answer which i think is contradicting with what you said in this answer.

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What is contradicting? We cannot do operand forward from stage X to stage X and do split phase-- because a single stage can only work in either the up cycle or low cycle. Also, there is no guarantee that EX stage can complete in just the up/down cycle unlike something like register read.