Performance Improvements via Peephole Optimization in Dynamic Binary Translation

The emergence of new instruction set architectures (ISAs) poses challenges in ensuring compatibility with legacy applications. Dynamic binary translation (DBT) serves as a crucial approach for achieving cross-ISA compatibility, enabling legacy applications to run compatibly with cross-ISAs. However, software-based translation encounters significant performance overhead, including substantial memory access and insufficient exploitation of target architecture features. The significant performance overhead challenges hinder the practical implementation of DBT. In this paper, we investigate a novel peephole optimization approach. First, we perform peephole analysis to identify redundant memory access and suboptimal instruction sequences. Next, we leverage live variable analysis to eliminate redundant memory-access instructions. Additionally, we bridge the gaps between cross-ISAs by exploiting ISA-specific features through instruction fusion. Finally, we implement the proposed optimization design using the open-source QEMU and extensively evaluate it on both ARM64 and SW64 platforms. The experimental results reveal that SPEC2006 benchmark effectively gets a maximum performance speedup of 1.52×, alongside a reduction in code size of up to 13.98%. These results affirm the effectiveness of our optimization approach in DBT performance and code sizes.