RAW hazard

Question

I have gone through several links related to raw harazd..
Some are saying, we consider RAW hazard between adjacent instruction only..EX
https://gateoverflow.in/17729/raw-dependencies
https://gateoverflow.in/116280/made-easy-co
https://gateoverflow.in/21299/war-raw-waw
https://gateoverflow.in/5295/data-hazards-raw-war-waw
https://gateoverflow.in/147731/raw-hazard

Some are saying for RAW hazard we need to look every instruction, be it adjacent or non adjacent .. EX
https://gateoverflow.in/35004/raw-hazard
https://gateoverflow.in/7409/how-many-dependencies-exists-the-following-set-instruction
https://gateoverflow.in/33350/cache-replacement-poicies
https://gateoverflow.in/11145/pipe
https://gateoverflow.in/34667/find-raw-dependencies
https://gateoverflow.in/753/gate2001-12

Iam confuse, in RAW dependency should we look for non adjacent instruction also ??

Comments

@joshi_nitish 

in this also we have dependency between sub and sw instruction but it will not create hazard in the pipeline because of this dependency.

ryt??

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yes, there will be no hazard.

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@joshi_nitish @shubhanshu thanks for clearing certain things out, I do believe adjacency and non adjacency need not matter while looking for dependency. Also it will depend on when result of Execution stage is going to available, if execution stage takes more number of cycle, then definitely non adjacent instruction will suffer because of dependency.
Taking reference of this question https://gateoverflow.in/3622/gate2006-it-78
Its previous year gate question, here if we consider only adjacent instruction, then no option matches, definitely we need to look for  non adjacent instructions as well.

Next to check for hazard, we need to draw pipeline diagram. If stalls are present then only that dependency will lead to hazard.

Correct me if iam still making any mistake.