A Dynamic-Static Combined Code Layout Reorganization Approach for Dynamic Binary Translation

Dynamic binary translation (DBT) has attracted much attention as a powerful technique for the runtime adaptation of software among different ISAs. It offers unprecedented flexibility in the control and modification of a program during the runtime. However, its inherent high overhead has perplexed researchers for many years. In order to reduce the overhead of DBT, this paper presents a dynamic-static combined approach to reorganize the layout of software cache. Under this approach, we first employ an emulating execution to collect the profile information and the translated target code. Especially, the path of execution flow will be tracked. In the static phase, based on the profile information collected in the previous stage, we first use the method of code replicating to build the traces, and then reorganize the layout of the target code by putting the hottest traces at the top of the software cache. Because of exact prediction and improved locality, the execution stream will concentrate on a small area with less control transfer. This approach can greatly reduce the overhead of DBT on the condition that the program runs repeatedly. Experimental results on executing the SPEC 2000 benchmarks show that our approach can reduce more than 30% run time on average.