Dependency VS Hazard

Question

Consider following program is executed on a 5 stage RISC pipeline and stages are IF, ID, EX, MA, WB.

IF = Instruction Fetch

ID = Instruction Decode and fetch register

EX  = Execution Stage

MA = Memory Access

WB = Write back register file

Program:-

I1) ADD R0, R1 R2

I2) ADD R3, R0 R4

I3) ADD R10, R0 R5

I4) ADD R11, R0 R6

I5) ADD R12, R0 R7

I6) ADD R13, R0 R8

I7) ADD R14, R0 R9

Calculate the number of RAW dependency and Hazards.(There is no Structural Dependency)

My Answers -> Dependencies = 6, hazards = 3.

Someone verify these answer.

Comments

@ayush, so for hazards we need to draw the diagram

---

yep!

---

@ayush.5 link given by you.. best answer say 9 , arjun sir answer say 11... I also think arjun sir answer is correct.. and yes ME test COA is kind of worst.. instructor have also some of the concepts wrong about cache.

Answer 1

Is it right please verify it

Comments

@Ram Swaroop How can you say that I1 and I3 have RAW dependency? I mean we go for immediate next instruction. There is only one RAW dependency. 

---

dependency doesn't need to be consecutive you can see here : question 3

https://cseweb.ucsd.edu/classes/wi12/cse141-a/solutions/assignment5-soln.pdf

---

@Ram Swaroop @sachin486

why are we not using "split phase" concept for Instruction2 at cycle 5?

---

yeah, there will be 2 hazard and by default split phase should be used