31 08 2020 E T Santambrogio

Pagina 1

Dipartimento di Elettronica e Informazione Politecnico di Milano 20133 Milano (Italia) Piazza Leonardo da Vinci, 32 Tel. (+39) 02-2399.3400 Fax (+39) 02-2399.3411 Advanced Computer Architecture August 31, 2020 Prof. Marco Santambrogio Name Last Name The student has to choose 2 out of the 3 exercises. If all the 3 exercises will be completed, just the 2 with the lowest score will be considered. This is an open book exam, which means the students can you use all their notes (we do not care of the format) but they cannot share their exams with anyone during the test. At the end of the exam, when the professor will call it, each student has to upload 1 PDF file (named using the “codice persona” – CodicePersona.pdf) using the Microsoft Form share via the Zoom chat at the beginning of the exam. In the first page of the uploaded PDF, the professor has to find the name and the surname of the student. Problem 1 (50%) Problem 2 (50%) Problem 3 (50%) Total (100%) Problem 1 Consider the above 5 stages pipelined architecture. Question 1: Indicate what kind of hazards can occur in this pipeline, motivating your answer Consider the following executed code. I1: ADDI R4, R0, R1 I2: ADDI R5, R0, R2 I3: BEQ R4, R5, 0x1000 I4: LW R7, 4(R6) I5: OR R5, R7, R5 I6: SW R5, 8(R6) Question 2: Complete the table and define how many clock cycles are needed. T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 I1 I2 I3 I4 I5 6 Question 3: Provide the architectural solutions to improve the performance for this code for the data hazards, motivating your answers and compute the performance improvement you can obtain. Considering the control hazard, what improvement can you provide with static branch prediction? How can you provide precise exceptions in this pipeline? Problem 2…