11 07 2023 E TS Silvano

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Surname (COGNOME) SOLUTION Name POLIMI Personal Code Signature Politecnico di Milano, 11 July, 2023 Course on Advanced Computer Architectures Prof. C. Silvano EX1 ( 5 points) EX2 ( 5 points) EX3 ( 5 points) Q1 ( 5 points) Q2 ( 5 points) QUIZZES ( 8 points) TOTAL (33 points) Course on Advanced Computer Architectures – prof. C. Silvano EXAM 11 July 2023 – Please write in CAPITAL LETTERS AND BLACK/BLUE COLORS!!! Page 1 - SOLUTION EXERCISE 1 – TOMASULO (5 points) Let’s consider the following assembly code to be executed on a CPU with dynamic scheduling based on TOMASULO algorithm with all cache HITS, a single Common Data Bus and: • 2 RESERVATION STATIONS (RS1, RS2) with 2 LOAD/STORE units (LDU1, LDU2) with latency 4 • 2 RESERVATION STATIONS (RS3, RS4) with 2 INTEGER ALU/BR units (ALU1, ALU2) with latency 2 • 2 RESERVATION STATIONS (RS5, RS6) with 2 FP ALU units (FPU, FPU2) with latency 4 Please complete the following table: INSTRUCTION ISSUE START EXEC WRITE RESULT Hazards Type RSi UNIT I1: lw $f1,A($r1) 1 2 6 -- RS1 LDU1 I2: addi $r2,$r1,4 I3: ld $f2,A($r2) I4: addi $r3,$r1,8 I5: ld $f3,A($r3) I6: fadd $f1,$f1,$f2 I7: fadd $f2,$f2,$f3 I8: fmul $f1,$f1,$f2 Calculate the CPI: CPI = _______________________________________________________________ Course on Advanced Computer Architectures – prof. C. Silvano EXAM 11 July 2023 – Please write in CAPITAL LETTERS AND BLACK/BLUE COLORS!!! Page 2 - SOLUTION Feedback: INSTRUCTION ISSUE START EXEC WRITE RESULT Hazards Type (*) RSi UNIT I1: lw $f1,A($r1) 1 2 6 -- RS1 LDU1 I2: addi $r2,$r1,4 2 3 5 -- RS3 ALU1 I3: ld $f2,A($r2) 3 6 10 RAW $r2 RS2 LDU2 I4: addi $r3,$r1,8 4 5 7 -- RS4 ALU2 I5: ld $f3,A($r3) 7 8 12 STRUCT RS1 (RAW $r3) RS1 LDU1 I6: fadd $f1,$f1,$f2 8 11 15 (RAW $f1), RAW $f2 RS5 FPU1 I7: fadd $f2,$f2,$f3 9 13 17 (RAW $f2)…