Design and Implementation of a Tracer Driver: Easy and Efficient Dynamic Analyses of Constraint Logic Programs

TL;DR

This paper introduces a flexible and efficient tracer driver for constraint logic programming that enables multiple dynamic analysis tools to operate with minimal overhead, improving debugging and analysis capabilities.

Contribution

The paper presents a novel tracer driver architecture that allows easy implementation of multiple dynamic analysis tools with low overhead, specifically tailored for constraint logic programming.

Findings

Negligible overhead in emulating existing execution views

Good performance with flexible event pattern specification

Effective integration of dynamic analyses in constraint logic programming

Abstract

Tracers provide users with useful information about program executions. In this article, we propose a ``tracer driver''. From a single tracer, it provides a powerful front-end enabling multiple dynamic analysis tools to be easily implemented, while limiting the overhead of the trace generation. The relevant execution events are specified by flexible event patterns and a large variety of trace data can be given either systematically or ``on demand''. The proposed tracer driver has been designed in the context of constraint logic programming; experiments have been made within GNU-Prolog. Execution views provided by existing tools have been easily emulated with a negligible overhead. Experimental measures show that the flexibility and power of the described architecture lead to good performance. The tracer driver overhead is inversely proportional to the average time between two traced events. Whereas the principles of the tracer driver are independent of the traced programming language, it is best suited for high-level languages, such as constraint logic programming, where each traced execution event encompasses numerous low-level execution steps. Furthermore, constraint logic programming is especially hard to debug. The current environments do not provide all the useful dynamic analysis tools. They can significantly benefit from our tracer driver which enables dynamic analyses to be integrated at a very low cost.