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Surname (Cognome) SOLUTION Name (Nome) POLIMI ID Number Signature (Firma) Politecnico di Milano, June 22nd, 2018 Course on Advanced Computer Architectures Prof. D. Sciuto, Prof. C. Silvano EX1 ( 5 points) EX2 ( 5 points) EX3 ( 6 points) Q1 ( 5 points) Q2 ( 5 points) SIX QUESTIONS ( 6 points) TOTAL (32 points) Course on Advanced Computer Architectures EXAM 22/06/2018 – Please write in CAPITAL LETTERS AND BLACK/BLUE COLORS!!! Page 1 - SOLUTION EXERCISE 1 – TOMASULO (5 points) Please consider the program in the table be executed on a CPU with dynamic scheduling based on TOMASULO algorithm with: x 2 RESERVATION STATIONS (RS1, RS2) + 2 LOAD/STORE unit (LDU1, LDU2) with latency 4 x 2 RESERVATION STATIONS (RS3, RS4) + 2 ALU/BR FUs (ALU1, ALU2) with latency 2 1. Please complete the TOMASULO TABLE by assuming all cache HITS ISTRUZIONE ISSUE START EXEC WRITE RESULT Hazards Type RSi UNIT lw $f1,0($r1) 1 2 6 RS1 LDU1 lw $f2,0($r1) 2 3 7 RS2 LDU2 fadd $f2,$f2,$f13 8 1 0 (RAW $f1) RAW $f2 RS3 ALU1 sw $f2,0($r1) 7 11 15 STRUCT RS1+ RAW $f2 RS1 LDU1 lw $f3,4($r1) 8 9 13 RS2 LDU2 lw $f4,4($r1) 14 15 19 STRUCT RS2 RS2 LDU1 fadd $f4,$f4,$f315 20 2 2 RAW $f4 RS3 ALU1 sw $f4,4($r1) 16 23 27 RAW $f4 RS1 LDU2 addi $r1,$r1,8 17 18 20 R S 4 A L U 2 2. Express the formula then compute the following metrics: x CPI = (#clock cyles / IC) = 27/10 =2.7 x IPC = 1/CPI = 1/ 2.7 = 0.37 Course on Advanced Computer Architectures EXAM 22/06/2018 – Please write in CAPITAL LETTERS AND BLACK/BLUE COLORS!!! Page 2 - SOLUTION EXERCISE 2: CACHE PERFORMANCE EVALUATION (5 points) Let us consider a computer with a memory hierarchy with L1 and L2 caches (including Instructions and Data). Suppose that in 1000 memory references there are 30 misses in L1 and 20 misses in L2. 1. What are the various miss rates? Miss…