22 01 2024 E S Silvano

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Surname (COGNOME) SOLUTION Name POLIMI Personal Code Signature Politecnico di Milano, 22 January, 2024 Course on Advanced Computer Architectures Prof. C. Silvano EX1 ( 5 points) EX2 ( 4 points) EX3 ( 3 points) EX4 ( 3 points) Q1 ( 5 points) Q2 ( 5 points) QUIZZES ( 8 points) TOTAL (33 points) Course on Advanced Computer Architectures – prof. C. Silvano EXAM 22 Jan. 2024 – Please write in CAPITAL LETTERS AND BLACK/BLUE COLORS!!! Page 1 - SOLUTION EXERCISE 1 – Tomasulo (5 points) Please consider the following assembly code: I1: lw $t2,VECTA($t6) I2: lw $t3,VECTB($t6) I3: lw $t4,VECTC($t6) I4: addi $t2,$t2,k I5: sw $t2,VECTA($t6) I6: add $t3,$t2,$t3 I7: add $t4,$t3,$t4 I8: sw $t4,VECTC($t6) to be executed on a CPU with dynamic scheduling based on TOMASULO algorithm with all cache HITS, a single Common Data Bus and: • 4 RESERVATION STATIONS (RS1, RS2, RS3, RS4) for 2 LOAD/STORE unit (LDU1, LDU2) with latency 6 • 2 RESERVATION STATIONS (RS5, RS6) for 2 ALU/BR FUs (ALU1, ALU2) with latency 2 1. Please complete the following table: INSTRUCTION ISSUE START EXEC WRITE RESULT Hazards Type RSi UNIT I1: lw $t2,VECTA($t6) 1 2 8 None RS1 LDU1 I2: lw $t3,VECTB($t6) 2 3 9 None RS2 LDU2 I3: lw $t4,VECTC($t6) I4: addi $t2,$t2,k I5: sw $t2,VECTA($t6) I6: add $t3,$t2,$t3 I7: add $t4,$t3,$t4 I8: sw $t4,VECTC($t6) 2. Calculate the CPI: CPI = _______________________________________________________________ Course on Advanced Computer Architectures – prof. C. Silvano EXAM 22 Jan. 2024 – 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 $t2,VECTA($t6) 1 2 8 None RS1 LDU1 I2: lw $t3,VECTB($t6) 2 3 9 None RS2 LDU2 I3: lw $t4,VECTC($t6) 3 9 15 STRUCT LDU1 RS3 LDU1 I4: addi $t2,$t2,k 4 9 11 RAW…