Binary translation is a powerful approach to support cross-architecture emulation of unmodified binaries in increasingly heterogeneous computing environments. However, binary translation systems face correctness issues, due to the strong-on-weak memory model mismatch (e.g., from x86-64 to Arm/RISC-V) for concurrent programs. Besides, the current landscape of binary translation systems is fundamentally limited in terms of completeness for static systems and performance for dynamic ones.

Abstract Burrow is a proof framework for weak memory mapping proofs. Those mappings appear as optimizations and translations between languages inside compilers and binary translators. However, their mechanized proofs, when defined over formal axiomatic weak memory semantics, are often large and complex. In this paper, we discuss the proof primitives provided by Burrow which simplify mechanizing those mapping proofs and help to prove many lemmas generally . To demonstrate the benefits of these primitives, we use Burrow to prove a mapping from x86 to Arm correct.

WebAssembly (WASM) is an immensely versatile and increasingly popular compilation target. It executes applications written in several languages (e.g., C/C++) with near-native performance in various domains (e.g., mobile, edge, cloud). Despite WASM's sandboxing feature, which isolates applications from other instances and the host platform, WASM does not inherently provide any memory safety guarantees for applications written in low-level, unsafe languages. To this end, we propose Cage, a hardware-accelerated toolchain for WASM that supports unmodified applications compiled to WASM and utilizes diverse Arm hardware features aiming to enrich the memory safety properties of WASM. Precisely, Cage leverages Arm's Memory Tagging Extension (MTE) to (i) provide spatial and temporal memory safety for heap and stack allocations and (ii) improve the performance of WASM's sandboxing mechanism. Cage further employs Arm's Pointer Authentication (PAC) to prevent leaked pointers from being reused by other WASM instances, thus enhancing WASM's security properties. We implement our system based on 64-bit WASM. We provide a WASM compiler and runtime with support for Arm's MTE and PAC. On top of that, Cage's LLVM-based compiler toolchain transforms unmodified applications to provide spatial and temporal memory safety for stack and heap allocations and prevent function pointer reuse. Our evaluation on real hardware shows that Cage incurs minimal runtime (<5.8%) and memory (<3.7%) overheads and can improve the performance of WASM's sandboxing mechanism, achieving a speedup of over 5.1%, while offering efficient memory safety guarantees.

Dynamic Binary Translation (DBT) is a powerful approach to support cross-architecture emulation of unmodified binaries. However, DBT systems face correctness and performance challenges, when emulating concurrent binaries from strong to weak memory consistency architectures. As a matter of fact, we report several translation errors in QEMU, when emulating x86 binaries on Arm hosts.

The emergence of new architectures create a recurring challenge to ensure that existing programs still work on them. Manually porting legacy code is often impractical. Static binary translation (SBT) is a process where a program’s binary is automatically translated from one architecture to another, while preserving their original semantics. However, these SBT tools have limited support to various advanced architectural features. Importantly, they are currently unable to translate concurrent binaries. The main challenge arises from the mismatches of the memory consistency model specified by the different architectures, especially when porting existing binaries to a weak memory model architecture.