Dominic Oehlert

Technische Universität Hamburg | TUHH

On the occasion of Peter Marwedel’s 70th anniversary, this article provides a survey over a decade of research in the field of compiler techniques for real-time systems. Ten years ago, during the EU-funded project Predator, it was him who led the work package on compilers. As will be shown in this survey, the work done in this domain had such a fun...

Modern embedded hard real-time systems feature multiple tasks running on multiple processing cores. Schedulability analysis of such systems is usually performed on an abstract system level with each task being represented as a black box with fixed timing properties. If timing constraints are violated, then optimizing the system on a code-level to a...

Modern hard real-time systems evolved from isolated single-core architectures to complex multi-core architectures which are often connected in a distributed manner. With the increasing influence of interconnections in hard real-time systems, the access behavior to shared resources of single tasks or cores becomes a crucial factor for the system’s o...

The hyperperiod defines the time span after which the temporal behavior of a periodical real-time system repeats. It is the key property which determines the complexity of both analysis and exhaustive simulation of a given system. Unfortunately, the hyperperiod may easily become very large. We introduce an ILP-based approach to modify the periods i...

Event arrival functions are commonly required in real-time systems analysis. Yet, event arrival functions are often either modeled based on specifications or generated by using potentially unsafe captured traces. To overcome this shortcoming, we present a compiler-based approach to safely extract event arrival functions. The extraction takes place...

Optimizing embedded systems often boils down to solving complex combinatorial optimization problems. Integer-Linear Programming (ILP) turned out to be a powerful tool to solve these problems, as beyond traditional constraints, Boolean variables may be used to model complex logical expressions and conditionals. One of the key technical aspects is to...

In this paper, we are interested in the implementation of control-command applications, such as the flight control system of an aircraft for instance, on multi-core hardware. Due to certification and safety issues, time-predictability - in the sense that the timing behavior must be analysable and validable off-line - is a mandatory feature. We pres...

Traditionally, design of embedded hard real-time software and timing analysis are decoupled from each other, leading to complicated design flows involving human interaction. Furthermore, traditional compilers optimize for average-case performance so that no tool support exists supporting the designer to systematically reduce Worst-Case Execution Ti...

Many embedded systems have to operate flawlessly over several years. One of the key issues which may cause computational errors over time are memory errors inflicted by aging effects. We propose a compiler-based optimization in order to mitigate such effects on data caches using SRAM memory cells.

Scratchpad Memory (SPM) allocation is a well-known technique for compiler-based code optimizations. Integer-Linear Programming has been proven to be a powerful technique to determine which parts of a program should be moved to the SPM. Although the idea is quite straight-forward in theory, the technique features several challenges when being applie...