Abstractions of sequences, functions and operators
摘要
We present theoretical and practical results on the order theory of lattices of functions, focusing on Galois connections that abstract (sets of) functions – a topic known as higher-order abstract interpretation. We are motivated by the challenge of inferring closed-form bounds on functions which are defined recursively, i.e. as the fixed point of an operator or, equivalently, as the solution to a functional equation. This has multiple applications in program analysis (e.g. cost analysis, loop acceleration, declarative language analysis) and in hybrid systems governed by differential equations. Our main contribution is a new family of constraint-based abstract domains for abstracting numerical functions,