Time-Safety Checking for Embedded Programs

Abstract

Giotto is a platform-independent language for specifying software for high-performance control applications. In this paper we present a new approach to the compilation of Giotto. Following this approach, the Giotto compiler generates code for a virtual machine, called the E machine, which can be ported to different platforms. The Giotto compiler also checks if the generated E code is time safe for a given platform, that is, if the platform offers sufficient performance to ensure that the E code is executed in a timely fashion that conforms with the Giotto semantics. Time-safety checking requires a schedulability analysis. We show that while for arbitrary E code, the analysis is exponential, for E code generated from typical Giotto programs, the analysis is polynomial. This supports our claim that Giotto identifies a useful fragment of embedded programs.

Supported in part by the DARPA SEC grant F33615-C-98-3614, MARCO GSRC grant 98-DT-660, AFOSR MURI grant F49620-00-1-0327, NSF grant CCR-9988172, and a Microsoft Research Fellowship.