GATE | GATE CS 2010 | Question 33

A 5-stage pipelined processor has Instruction Fetch(IF),Instruction Decode(ID),Operand Fetch(OF),Perform Operation(PO)and Write Operand(WO)stages.The IF,ID,OF and WO stages take 1 clock cycle each for any instruction.The PO stage takes 1 clock cycle for ADD and SUB instructions,3 clock cycles for MUL instruction,and 6 clock cycles for DIV instruction respectively.Operand forwarding is used in the pipeline.What is the number of clock cycles needed to execute the following sequence of instructions?

     Instruction           Meaning of instruction
  I0 :MUL R2 ,R0 ,R1	      R2 ¬ R0 *R1
  I1 :DIV R5 ,R3 ,R4  	      R5 ¬ R3/R4
  I2 :ADD R2 ,R5 ,R2	      R2 ¬ R5+R2
  I3 :SUB R5 ,R2 ,R6	      R5 ¬ R2-R6