26,098 papers · page 500 of 1,305
Memory access latency continues to be a dominant bottleneck in a large class of applications on modern architectures. To optimize memory performance, it is important to utilize the locality in the memory hierarchy. Structure splitting can significantly improve memory locality. Ho…
Many problems in science and engineering are in practice modeled and solved through matrix computations. Often, the matrices involved have structure such as symmetric or triangular, which reduces the operations count needed to perform the computation. For example, dense linear sy…
For C programs, flow-sensitivity is important to enable pointer analysis to achieve highly usable precision. Despite significant recent advances in scaling flow-sensitive pointer analysis sparsely for sequential C programs, relatively little progress has been made for multithread…
A program subject to a Return-Oriented Programming (ROP) attack usually presents an execution trace with a high frequency of indirect branches. From this observation, several researchers have proposed to monitor the density of these instructions to detect ROP attacks. These techn…
Several applications may trade-off output quality for energy efficiency by computing only an approximation of their output. Current approaches to software-based approximate computing often require the programmer to specify parts of the code or data structures that can be approxim…
Graphics Processing Units have emerged as powerful accelerators for massively parallel, numerically intensive workloads. The two dominant software models for these devices are NVIDIA’s CUDA and the cross-platform OpenCL standard. Until now, there has not been a fully open-source …
Task based programming models (e.g., Cilk, Intel TBB, X10, Java Fork-Join tasks) simplify multicore programming in contrast to programming with threads. In a task based model, the programmer specifies parallel tasks and the runtime maps these tasks to hardware threads. The runtim…
Existing loop vectorization techniques can exploit either intra- or inter-iteration SIMD parallelism alone in a code region if one part of the region vectorized for one type of parallelism has data dependences (called mixed-parallelism-inhibiting dependences) on the other part of…
We describe the formalisation in Coq of a proof that the numbers `e` and `pi` are transcendental. This proof lies at the interface of two domains of mathematics that are often considered separately: calculus (real and elementary complex analysis) and algebra. For the work on calc…
Code obfuscation is emerging as a key asset in security by obscurity. It aims at hiding sensitive information in programs so that they become more difficult to understand and reverse engineer. Since the results on the impossibility of perfect and universal obfuscation, many obfus…
In Separation Logic, representation predicates are used to describe mutable data structures, by establishing a relationship between the entry point of the structure, the piece of heap over which this structure spans, and the logical model associated with the structure. When a dat…
We formalize an algorithm to change the representation of a poly- nomial to a Newton power series. This provides a way to compute efficiently polynomials whose roots are the sums or products of roots of other polynomials, and hence provides a base component of efficient computati…
Hammers are tools for employing external automated theorem provers (ATPs) to improve automation in formal proof assistants. Strong automation can greatly ease the task of developing formal proofs. An essential component of any hammer is the translation of the logic of a proof ass…
In homotopy type theory, we construct the propositional truncation as a colimit, using only non-recursive higher inductive types (HITs). This is a first step towards reducing recursive HITs to non-recursive HITs. This construction gives a characterization of functions from the pr…
I will discuss the importance, uses, and future directions of formal verification from the point of view of a mathematical foundationalist. These include issues of certainty, proof structure, and (finitary) completeness and decidability.
Differential dynamic logic is a logic for specifying and verifying safety, liveness, and other properties about models of cyber-physical systems. Theorem provers based on differential dynamic logic have been used to verify safety properties for models of self-driving cars and col…
In this paper we explore the possibility of emulating the Mizar environment as close as possible inside the Isabelle logical framework. We introduce adaptations to the Isabelle/FOL object logic that correspond to the logic of Mizar, as well as Isar inner syntax notations that cor…
This paper presents new features recently implemented in the theorem prover Vampire, namely support for first-order logic with a first class boolean sort (FOOL) and polymorphic arrays. In addition to having a first class boolean sort, FOOL also contains if-then-else and let-in ex…
In this paper we present a stepwise refinement based top-down approach to verified imperative data structures. Our approach is modular in the sense that already verified data structures can be used for construction of more complex data structures. Moreover, our data structures ca…
This paper presents a construction of the real algebraic numbers with executable arithmetic operations in Isabelle/HOL. Instead of verified resultants, arithmetic operations on real algebraic numbers are based on a decision procedure to decide the sign of a bivariate polynomial (…