2. WHAT IS INSTRUCTION PIPELINE
A PIPELINING IS A SERIESOF STAGES, WHERE SOME WORKIS DONEAT EACH STAGE
IN PARALLEL.
THE STAGESARE CONNECTEDONE TO THE NEXTTO FORMA PIPE INSTRUCTIONS
ENTERAT ONE END, PROGRESSTHROUGH THE STAGES, ANDEXIT AT THE OTHER
END.
3. DEFINITION
PIPELINING IS AN SPEED UP TECHNIQUE WHERE
MULTIPLE INSTRIUCTIONS ARE OVERLAPPED IN
EXCUTION ON A PROCESSOR.
4.
5.
6. PIPELINING : PROCESSORS
COMPUTER , LIKE LAUNDRY , TYPICALLY PERFORMEDTHE EXACT SAME STEPS FOR
EVERYINSTRUCTION:
-FETCHAN INSTRUCTIONFROMMEMORY
-DECODE THE INSTRUCTION
-EXECUTETHE INSTRUCTION
-READMEMORY TO GET INPUT
-WRITETHE RESULT BACK TO MEMORY.
7. OPERATION OF INSTRUCTION PIPELINE
INSTRUCTIONPIPELINEHAS SIX OPERATION:-
FETCHINSTRUCTION(FI)
DECODEINSTRUCTION(DI)
CALCULATE OPERANDS(CO)
FETCHOPERANDS(FO)
EXECUTE INSTRUCTIONS(EI)
WRITERESULT(WR)
8. LETS DESCRIBE THE OPERATIONS
INSTRUCTIONS FETCH:
THE IF STAGEIS RESPONSIBLEFOR OBTAININGTHE REQUESTEDINSTRUCTIONFROMMEMORY.THE
INSTRUCTIONAND THE PROGRAMMECOUNTERARE STOREDIN THE REGISTER AS TEMPORARY STORAGE.
DECODEINSTRUCTION:
THE DI STAGEIS RESPONSIBLEFOR DECODINGTHE INSTRUCTIONAND SENDINGOUT THE VARIOUS
CONTROLLINESTO THE OTHERPARTSOF THE PROCESSOR.
9. CALCULATE OPERANDS:
THE CO STAGE IS WHERE ANY CALCULATIONS ARE PERFORMEDTHE MAIN
COMPONENT IN THIS STAGEIS THE ALU. THE ALU IS MADEUP OF ARITHMETIC, LOGIC
AND CAPABILITIES.
FETCHOPERANDS & EXECUTE INSTRUCTION :
THE FO AND EI STAGESARE RESPONSIBLE FOR STORINGAND LODINGVALUES TO AND
FROMMEMORY.THEYALSORESPONSIBLEFOR INPUT AND OUTPUT FROMTHE
PROCESSOR RESPECTIVELY.
10. WRITE OPERANDS :
THE WO STAGE IS RESPONSIBLE FOR WRITING THE
RESULT OF A CALCULATION , MEMORY ACCESS
OR INPUT INTO THE REGISTER FILE.
12. ADVANTAGES
PIPELINING MAKES EFFICIENTUSE OF RESOURCES.
QUICKER TIME OF EXECUTION OF LARGE NUMBER OF INSTRUCTION.
THE PARALLELISM IS INVISIBLE TO THE PROGRAMMER.
13. CAN PIPELINING GET US INTO TROUBLE?
YES!
THIS IS CALLEDHAZARD
THERE ARE THREE DIFFERENTTYPES OF HAZARD
STRUCTURALHAZARDS , DATAHAZARDS & CONTROLHAZARDS
14. STRUCTURALHAZARDS:-ATTEMPTTO USE THESAMERESOURCEBY TWODIFFERENT
INSTRUCTIONSAT THESAMETIME
DATAHAZARDS :-ATTEMPTTO USE DATABEFOREIT IS READY
AN INSTRUCTIONSSOURCEOPERANDSAREPRODUCEDBY A PRIORINSTRUCTIONSSTILLIN
THEPIPELINE.
CONTROLL HAZARDS:- ATTEMPTTO MAKEA DECISIONABOUTPROGRAMCONTROL FLOW
BEFORETHE CONDITIONHAS BEENEVALUTEDANDTHENEWPC TARGETADDRESSCALCULATED.
15. ACKNOWLEDGMENTS
I WOULDLIKETO EXPRESSMY SPECIALTHANKSTO MY COMPUTERORGANIZATIONTEACHER
(SOUVIKSIR) WHOGAVEME THE GOLDENOPPORTUNITYTODO THIS WONDERFUL PROJECTON THE
TOPIC(INSTRUCTIONS PIPELINE) .WHICHHELPEDME TODO A LOTSOF RESEARCHANDI CAMETO
KNOWABOUTSO MANYNEWTHINGS.I AMREALLYTHANKFUL TOTHEM.SECONDLYI WOULDLIKE
TO THANKSMY FRIENDS& PARENTSWHOHELPEDMEIN DOINGTHISPROJECTWITHINLIMITED
TIMEFRAME.
