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Politecnico di Milano FACOLTÀ DI INGEGNERIA DELL’INFORMAZIONE Sistemi Embedded 1 A.A. 2014-2015 – Exam date: 25 Feb 2015 Prof. William FORNACIARI Surname (readable)........................................ Name (readable)............................ Matr................................................................. Signature........................................ Q1 Q2 Q3 Q4 TOT NOTES It is forbidden to refer to texts or notes of any kind as well as interact with their neighbors. Anyone found in possession of documents relating to the course, although not directly relevant to the subject of the examination will cancel the test. It is not allowed to leave during the first half hour, the task must still be returned, even if it is withdrawn. The presence of the writing (not delivered) implies the renunciation of any previous ratings. Question Q1 (10 points) Referring to the Design Space Exploration (DSE), the students is required to discuss: • the main goals and problems addressed by the DSE and the benefits of an automated DSE • what is the concept of robust optimization, possibly with an example • the importance of the analysis metrics and, in particular, the concept of “fidelity” 1/7 2/7 Question Q2 a) (3 points) Describe the concept of event-based simulation. Focusing on GEM5 describe the main event-based infrastructure of the simulator. Why GEM5 implements two different “times”? How does it use them? In the event-based simulation everything is governed by software events that mimic real hardware events. An event could be an interrupt, the rising front of the clock etc, that triggers further actions. For example at each rising front of the clock a D flip-flop registers the D value and propagates it to its output Q. In the software an event is an object with an…