The Challenges of Hardware Synthesis from C-like Languages

The relentless increase in the complexity of integrated circuits we can fabricate imposes a continuing need for ways to describe complex hardware succinctly. Because of their ubiquity and flexibility, many have proposed to use the C and C++ languages as specification languages for digital hardware. Yet, tools based on this idea have seen little commercial interest. In this paper, I argue that C/C++ is a poor choice for specifying hardware for synthesis and suggest a set of criteria that the next successful hardware description language should have

Model Extraction of Legacy C Code in SCCharts

With increasing volumes of developed software and steadily growing complexity of these systems, software engineers struggle to manually maintain the vast amount of legacy code. Therefore, it is of interest to create a system which supports the documentation, maintenance, and reusability of software and its legacy code. The approach presented here automatically derives SCCharts models out of C code. These models can be used as visual documentation. By applying focus and context methods important parts of the model can be highlighted and may grant a better understanding of the overall software. Additionally, the models can also be used as a source to create new state-of-the-art code for various languages and platforms, such as C code or VHDL, using automatic code generators

A framework for automatically generating optimized digital designs from C-language loops

Reconfigurable computing has the potential for providing significant performance increases to a number of computing applications. However, realizing these benefits requires digital design experience and knowledge of hardware description languages (HDLs). While a number of tools have focused on translation of high-level languages (HLLs) to HDLs, the tools do not always create optimized digital designs that are competitive with hand-coded solutions. This work describes an automatic optimization in the C-to-HDL transformation that reorganizes operations between pipeline stages in order to reduce critical path lengths. The effects of this optimization are examined on the MD5, SHA-1, and Smith-Waterman algorithms. Results show that the optimization results in performance gains of 13%-37% and that the automatically-generated implementations perform comparably to hand-coded implementations

A framework for automatically generating optimized digital designs from C-language loops

Reconfigurable computing has the potential for providing significant performance increases to a number of computing applications. However, realizing these benefits requires digital design experience and knowledge of hardware description languages (HDLs). While a number of tools have focused on translation of high-level languages (HLLs) to HDLs, the tools do not always create optimized digital designs that are competitive with hand-coded solutions. This work describes an automatic optimization in the C-to-HDL transformation that reorganizes operations between pipeline stages in order to reduce critical path lengths. The effects of this optimization are examined on the MD5, SHA-1, and Smith-Waterman algorithms. Results show that the optimization results in performance gains of 13%-37% and that the automatically-generated implementations perform comparably to hand-coded implementations

Guarded atomic actions and refinement in a system-on-chip development flow: bridging the specification gap with Event-B

Modern System-on-chip (SoC) hardware design puts considerable pressure on existing design and verification flows, languages and tools. The Register Transfer Level (RTL)description, which forms the input for synchronous, logic synthesis-driven design is at too low a level of abstraction for efficient architectural exploration and re-use. The existing methods for taking a high-level paper specification and refining this specification to an implementation that meets its performance criteria is largely manual and error-prone and as RTL descriptions get larger, a systematic design method is necessary to address explicitly the timing issues that arise when applying logic synthesis to such large blocks.Guarded Atomic Actions have been shown to offer a convenient notation for describing microarchitectures that is amenable to formal reasoning and high-level synthesis. Event-B is a language and method that supports the development of specifications with automatic proof and refinement, based on guarded atomic actions. Latency-insensitive design ensures that a design composed of functionally correct components will be independent of communication latency. A method has been developed which uses Event-B for latency-insensitive SoC component and sub-system design which can be combined with high-level, component synthesis to enable architectural exploration and re-use at the specification level and to close the specification gap in the SoC hardware flow

Dynamic task scheduling and binding for many-core systems through stream rewriting

This thesis proposes a novel model of computation, called stream rewriting, for the specification and implementation of highly concurrent applications. Basically, the active tasks of an application and their dependencies are encoded as a token stream, which is iteratively modified by a set of rewriting rules at runtime. In order to estimate the performance and scalability of stream rewriting, a large number of experiments have been evaluated on many-core systems and the task management has been implemented in software and hardware.In dieser Dissertation wurde Stream Rewriting als eine neue Methode entwickelt, um Anwendungen mit einer großen Anzahl von dynamischen Tasks zu beschreiben und effizient zur Laufzeit verwalten zu können. Dabei werden die aktiven Tasks in einem Datenstrom verpackt, der zur Laufzeit durch wiederholtes Suchen und Ersetzen umgeschrieben wird. Um die Performance und Skalierbarkeit zu bestimmen, wurde eine Vielzahl von Experimenten mit Many-Core-Systemen durchgeführt und die Verwaltung von Tasks über Stream Rewriting in Software und Hardware implementiert