LAST: An Efficient In-place Static Binary Translator for RISC Architectures

The lack of software has been a persistent issue for emerging instruction set architecture (ISA). To overcome this challenge, binary translation has emerged as a widely adopted solution, enabling programs written for older ISA to run on new ones. In the past, dynamic binary translation (DBT) was commonly utilized for software migration, but this technique required dynamic translation and often suffered from suboptimal efficiency. In contrast, Static binary translation (SBT) is an offline technique for translating binary code without runtime translation overhead. Existing SBT systems always employ address mapping tables to handle the address relocation problem, but this approach introduces performance overhead and leads to issues with indirect jump correctness. To address these limitations, we propose a novel static in-place instruction translation method for reduced-instruction set computing (RISC) architectures. This method ensures that the address of the guest program remains unchanged after translation, leveraging the regular length of various RISC instructions. We have implemented this method in a portable SBT tool called LAST, specifically designed to run MIPS or RISCV programs on the LoongArch platform. Based on the SPEC CPU2000 benchmark results, LAST achieves over 80% performance compared to the native LoongArch program, demonstrating its effectiveness and efficiency.