We describe a tool, called AX, that can be used in combination with the model checker SPIN to efficiently verify logical properties of distributed software systems implemented in ANSI-standard C [18]. AX, short for Automaton eXtractor, can extract verification models from C code at a user defined level of abstraction. Target applications include telephone switching software, distributed operati...

Code transformations are a very effective method of parallelizing and improving the efficiency of programs. Unfortunately most compiler systems require implementing separate (sub-)programs for each transformation. This paper describes a different approach. We designed and implemented a fully programmable transformation engine. It can be programmed by means of a transformation language. This lan...

Automatic software instrumentation is usually done at the machine level or is targeted at speciic program behavior for use with a particular monitoring application. This paper describes CCI, an automatic software instru-mentation tool for ANSI C designed to serve a broad range of program execution monitors. CCI supports high level instrumentation for both application-speciic behavior as well as...

Lightweight wheelchairs are characterized by their low cost and limited range of adjustment. Our study evaluated three different folding lightweight wheelchair models using the American National Standards Institute/Rehabilitation Engineering Society of North America (ANSI/RESNA) standards to see whether quality had improved since the previous data were reported. On the basis of reports of incre...

In scienti c computing, we often require the derivatives @f=@x of a function f expressed as a program with respect to some input parameter(s) x, say. Automatic di erentiation (AD) techniques augment the program with derivative computation by applying the chain rule of calculus to elementary operations in an automated fashion. This article introduces ADIC (Automatic Di erentiation of C), a new A...