Dynamic Optimization Techniques

As has been emphasized throughout this book, it is necessary a high level of adaptability to cope with the high heterogeneous behavior of recent applications. At the same time, binary code compatibility is mandatory, so the large amount of already existing software can be reused without any kind of modification. In this scenario, this chapter discusses dynamic optimization techniques, how they can be used to improve performance, how they maintain binary compatibility and some case studies. The chapter starts presenting Binary translation. Its main concepts are clarified, as well as the main challenges that a binary translator mechanism must handle to work properly. The section ends with a detailed view of some examples of Binary Translation machines. Then, Reuse is discussed, and diverse types of it are covered: instruction reuse, value prediction, basic block, trace reuse and dynamic trace memoization. Furthermore, according to the discussion made in Chap.3, even though reconfigurable systems present huge potentials in terms of performance and energy, they alone cannot deal with the high heterogeneous behavior of recent applications neither maintain binary compatibility. Therefore, this chapter ends presenting approaches that use reconfigurable architectures together with mechanisms that somehow reassembles the behavior of the dynamic optimization techniques.