241-440 @ w.s. 24-440 computer system design lecture 7 wannarat suntiamorntut

241-440 @ W.S.

2 -4 440 Computer Syste

mDesign Lecture 7

Wannarat Suntiamorntut

241-440 @ W.S.

PIPELINE

241-440 @ W.S.

Pipeline in the R eal world

30Washer takes minutes 33 333333330 33 333333330 33 333333330

241-440 @ W.S.

Sequential Laundry

8 4take hours for loads

241-440 @ W.S.

Pipeline laundr y

333 3 333333.5 4

241-440 @ W.S.

Datapath opera tion in MIP

333333 / 3333 333 33

241-440 @ W.S.

Apply Pipeline

241-440 @ W.S.

Pipeline Executio n Representation

241-440 @ W.S.

Pipeline give us If we would like to execute 100 instructi

333 33:45/ 11 00= 4 500 Multiple cycle : 10ns/cycle x 4.6 CPI x 10

0 = 4600 ns Pipeline (Ideal) : 10ns/cycle x (1 CPI x 10

0 + 4 cycle drain) = 1040 ns

241-440 @ W.S.

Comparison : singl e, multiple, pipeline

241-440 @ W.S.

Pipeline Hazard Structure Hazard

Same resources at the same time Data Hazard

Instruction depend on result of priorinstruction

Control Hazard Br anch I nst r uct i on

241-440 @ W.S.

Single Memory ( Structure H.)

241-440 @ W.S.

Control H. Solution

241-440 @ W.S.

Control H. Solut ion (Predict)

241-440 @ W.S.

Control H. Solut ion (Delay)

241-440 @ W.S.

Data H. 333 r1 , 2, 3 333 2 r1 336 and 7r , r1 , 5 33 4r , r1 338

241-440 @ W.S.

Data H. on R1

241-440 @ W.S.

Data H. (By pas sing) with Load

Must Solve by Delay / Stall

241-440 @ W.S.

Pipelined Processor

241-440 @ W.S.

Control and Datapath

241-440 @ W.S.

-Load and R type

Pipeline Conflict or Structural Hazar3

241-440 @ W.S.

Observation Each unit can only be used by one instruction

Each unit must be used at the same stage for all instructions

3333 33 33333 3333 33333332

241-440 @ W.S.

1. Insert Bubble into pipeline

241-440 @ W.S.

-2. Delay R type

241-440 @ W.S.

Modifies Contro l & Datapath

241-440 @ W.S.

Datapath + Control

241-440 @ W.S.

Try it 10 lw 1 2 35r , r ( )14 addl 2 2 3r , r ,20 sub 3 4 5r , r , r24 beq 6 7 100r , r ,30 333 8, 9, 17r r34 add 10 11 12r , r , r

100 and 13 14 15r , r ,33333 333333

241-440 @ W.S.

10Fetch :

241-440 @ W.S.

Fetch1 4 / Deco de 10

241-440 @ W.S.

3 3332 0

de 14, Execute10

241-440 @ W.S.

24Fetch , Dec 20 14, Exec ,

Mem10

241-440 @ W.S.

F3 0 ,Dc 2 4 , E 20 14, Mem ,

10WB

241-440 @ W.S.

334 3 0

24 20, Mem , 14

241-440 @ W.S.

100F , 3 4 3, 30 24, Mem ,

20

241-440 @ W.S.

104 10F , Dc 0,34 , Mem30,

24

241-440 @ W.S.

110 10F , Dc 4 100, E , Mem

34 30

241-440 @ W.S.

114 110F , Dc 104 100, E , Mem ,33 34

241-440 @ W.S.

8Next on Lecture