1,971 papers · page 9 of 99
Exact probabilistic inference is a requirement for many applications of probabilistic programming languages (PPLs) such as in high-consequence settings or verification. However, designing and implementing a PPL with scalable high-performance exact inference is difficult: exact in…
Large language models (LLMs) have achieved notable success in code generation. However, they still frequently produce uncompilable output because their next-token inference procedure does not model formal aspects of code. Although constrained decoding is a promising approach to a…
Semantics-Guided Synthesis (SemGuS) provides a framework to specify synthesis problems in a solver-agnostic and domain-agnostic way, by allowing a user to provide both the syntax and semantics of the language in which the desired program should be synthesized. Because synthesis a…
Using program synthesis to select instructions for and optimize input programs is receiving increasing attention. However, existing synthesis-based compilers are faced by two major challenges that prohibit the deployment of program synthesis in production compilers: exorbitantly …
We introduce Thrust, a new verification tool for ensuring functional correctness in Rust, distinguished by its strengths in automated verification, including the synthesis of inductive invariants for loops and recursive functions. Thrust is built on a novel dependent refinement t…
We introduce a version of probabilistic Kleene algebra with angelic nondeterminism and a corresponding class of automata. Our approach implements semantics via distributions over multisets in order to overcome theoretical barriers arising from the lack of a distributive law betwe…
We report the first formal verification of a lock-free list, skiplist, and a skiplist-based priority queue against a strong specification in relaxed memory consistency (RMC). RMC allows relaxed behaviors in which memory accesses may be reordered with other operations, posing two …
Our RLibm project has recently proposed methods to generate a single implementation for an elementary function that produces correctly rounded results for multiple rounding modes and representations with up to 32-bits. They are appealing for developing fast reference libraries wi…
The selection monad on a set consists of selection functions. These select an element from the set, based on a loss (dually, reward) function giving the loss resulting from a choice of an element. Abadi and Plotkin used the monad to model a language with operations making choices…
Actors are lightweight reactive processes that communicate by asynchronous message-passing. Actors address common problems like concurrency control and fault tolerance, but resource management remains challenging: in all four of the most popular actor frameworks (Pekko, Akka, Erl…
The C and C++ languages define hundreds of cases as having undefined behavior (UB). These include, for example, corner cases where different CPU architectures disagree on the semantics of an instruction and the language does not want to force a specific implementation (e.g., shif…
Large-scale, revenue-critical application services are often written in Java or other memory-safe languages whose type systems do not expose immutable state. Such applications are especially exposed to garbage collection performance overheads because latency, throughput, and memo…
Blockchains operating at the global scale demand high-performance byzantine fault-tolerant (BFT) consensus protocols. Most classic PBFT-like protocols suffer from an issue known as the leader bottleneck, which severely limits their throughput and resource utilization. Recently, D…
We define webs to be the collections of producers and consumers (e.g., functions and calls) in a program that are constrained: in higher-order languages, multiple functions can flow to the same call, all of which must agree on an interface (e.g., calling convention). We argue tha…
There are many state-of-the-art techniques for loop bound analysis. Most of them target an upper bound for a given program, and others find a lower bound. Exact bound analysis still remains largely unexplored, but it offers new applications. To compute an exact bound for a progra…
Nondeterminism introduced by race conditions and message reorderings makes parallel and distributed programming hard. Nevertheless, promising approaches such as LVars and CRDTs address this problem by introducing a partial order structure on shared state that describes how the st…
Sparse data structures are ubiquitous in modern computing, and numerous formats have been designed to represent them. These formats may exploit specific sparsity patterns, aiming to achieve higher performance for key numerical computations than more general-purpose formats such a…
Generating random variates is a fundamental operation in diverse areas of computer science and is supported in almost all modern programming languages. Traditional software libraries for random variate generation are grounded in the idealized "Real-RAM" model of computation, wher…
We present Dependent Lambek Calculus (LambekD), a domain-specific dependent type theory for verified parsing and formal grammar theory. In LambekD, linear types are used as a syntax for formal grammars, and parsers can be written as linear terms. The linear typing restriction pro…
Equality saturation has gained significant interest as a powerful optimization and reasoning technique. At its heart is the e-graph data structure, that space-efficiently represents equal sub-terms uniquely. An important open problem in this context is extending this efficient re…