SUB X5, X15, X4 Suppose we modify the pipeline so that it has only one memory (that handles both instructions and data). In this case, there will be a structural hazard every time a program needs to fetch an instruction during the same cycle in which another instruction accesses data. 1- Draw a pipeline diagram to show where the code above will stall. 2- In general, is it possible to reduce the number of stalls/ NOPs resulting from this structural hazard by reordering code (reordering the instructions)? 3- Must this structural hazard be handled in hardware? We have seen that data hazards can be eliminated by adding NOPs to the code. Can you do the same with this structural hazard? If so, explain how. If not, explain why not. 4- If we run the code above on a single-cycle computer, what kind of hazards are there?

SUB X5, X15, X4 Suppose we modify the pipeline so that it has only one memory (that handles both instructions and data). In this case, there will be a structural hazard every time a program needs to fetch an instruction during the same cycle in which another instruction accesses data. 1- Draw a pipeline diagram to show where the code above will stall. 2- In general, is it possible to reduce the number of stalls/ NOPs resulting from this structural hazard by reordering code (reordering the instructions)? 3- Must this structural hazard be handled in hardware? We have seen that data hazards can be eliminated by adding NOPs to the code. Can you do the same with this structural hazard? If so, explain how. If not, explain why not. 4- If we run the code above on a single-cycle computer, what kind of hazards are there?

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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