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Developers nowadays regularly use numerous programming languages with different characteristics and trade-offs. Unfortunately, implementing a software verifier for a new language from scratch is a large and tedious undertaking, requiring expert knowledge in multiple domains, such as compilers, verification, and constraint solving. Hence, only a tiny fraction of the used languages has readily available software verifiers to aid in the development of correct programs. In the past decade, there has been a trend of leveraging popular compiler intermediate representations (IRs), such as LLVM IR, when implementing software verifiers. Processing IR promises out-of-the-box multi- and cross-language verification since, at least in theory, a verifier ought to be able to handle a program in any programming language (and their combination) that can be compiled into the IR. In practice though, to the best of our knowledge, nobody has explored the feasibility and ease of such integration of new languages. In this paper, we provide a procedure for adding support for a new language into an IR-based verification toolflow. Using our procedure, we extend the SMACK verifier with prototypical support for 6 additional languages. We assess the quality of our extensions through several case studies, and we describe our experience in detail to guide future efforts in this area. 

Virtually all real-valued computations are carried out using floating-point data types and operations. With increasing emphasis on overall computational efficiency, compilers are increasingly attempting to optimize floating-point expressions. Practical reasoning about the correctness of these optimizations requires error analysis procedures that are rigorous (ideally, they can generate proof certificates), can handle a wide variety of operators (e.g., transcendentals), and handle all normal programmatic constructs (e.g., conditionals and loops). Unfortunately, none of today’s approaches can achieve this combination. This position paper summarizes recent progress achieved in the community on this topic. It then showcases the component techniques present within our own rigorous floating-point precision tuning framework called FPTuner—essentially offering a collection of “grab and go” tools that others can benefit from. Finally, we present FPTuner’s limitations and describe how we can exploit contemporaneous research to improve it.