Propan is a system that allows for the generation of machine-dependent postpass optimisations and analyses on assembly level. It has been especially designed to perform high-quality optimisations for irregular architectures. All information about the target architecture is specied in the machine description language Tdl. For each target architecture a phase-coupled code optimiser is generated which can perform integrated global instruction scheduling, register reassignment, and resource allocation by integer linear programming (ILP). All relevant hardware characteristics of the target processor are precisely incorporated in the generated integer linear programs. Two dierent ILP models are available so that the most appropriate modelling can be selected individually for each target architecture. The integer linear programs can be solved either exactly or by the use of ILP-based approximations. This allows for high quality solutions to be calculated in acceptable time. A set of practic...

The development of application-specific instruction -set processors (ASIP) is currently the exclusive domain of the semiconductor houses and core vendors. This is due to the fact that building such an architecture is a difficult task that requires expertise in different domains: application software development tools, processor hardware implementation, and system integration and verification. This article presents a retargetable framework for ASIP design which is based on machine descriptions in the LISA language. From that, software development tools can be generated automatically including high-level language C compiler, assembler, linker, simulator, and debugger frontend. Moreover, for architecture implementation, synthesizable hardware description language code can be derived, which can then be processed by standard synthesis tools. Implementation results for a low-power ASIP for digital video broadcasting terrestrial acquisition and tracking algorithms designed with the presented methodology will be given. To show the quality of the generated software development tools, they are compared in speed and functionality with commercially available tools of state-of-the-art digital signal processor and µC architectures.

When developing software for embedded systems, the set of essential tools includes a compiler and an instruction set simulator. Since software and hardware are often designed in parallel, the tools must be easily adaptable to the changing target architecture. For the compiler, its back-end (the code generator) must be retargetable. Abstraction from the target machine is the key to an automated approach. Additionally, abstraction from tool-internal strategies permits the utilization of a unified machine description for all tools. In this chapter, the machine description formalism nML is presented along with the retargetable code generator Cbc and the instruction set simulation environment Sigh/Sim. 1 INTRODUCTION For the realization of retargetable software development tools such as a code generator and an instruction set simulator, several aspects of the potential target machines must be modeled in an abstract manner. These machine models are necessary to formalize the tool's methods...

In this paper, we describe how cycle-accurate processor behavior may be eciently described using Abstract State Machines (ASMs).

An experimental set of tools that generate instruction set simulators, assemblers, and disassemblers from a single description was developed to test if retargetable development tools would work for commercial DSP processors and microprocessors. The processor instruction set was described using a language called nML. The TMS320C50 DSP processor and the ARM7 microprocessor were modeled in nML. The resulting instruction set models execute about 25,000 instructions per second, and compiled instruction set simulation models execute about 150,000 instructions per second. The viability of this approach and the deficiencies of nML are discussed.

Rapidly increasing design and manufacturing non-recurring engineering (NRE) costs are prompting a shift in electronic design from hardwired application specific integrated circuits (ASICs) to the use of software on programmable platforms. However, in order to minimize the power and performance overhead of such processors, we are seeing the introduction of domain or application specific processors such as network and communication processors. The design of such specialized processors requires software development tools such as simulators and compilers. In order to quickly develop these tools for multiple design points under consideration, it is highly desirable to have them synthesized from formal processor descriptions written in Architecture Description Languages (ADLs). In this paper, we present the Mescal Architecture Description Language (MADL). MADL features a two-layer structure, a core layer and an annotation layer. The core layer is based on a

Introduction Mobile and personal communication systems, and multi-media are among the most prominently growing sectors of the electronics industry today. As an illustration, Figure 1 gives an indication of the volume of some personal communication applications in the European market. New business and home applications are emerging, using advanced communication media such as satellite links, cellular radio, or high-speed optical networks. The success of these developments will however depend to a great extent on the ability to realise complex digital signal processing functionalities in cost-efficient VLSI chips. 1990 1992 1994 1996 40 30 20 10 0 Million users Cordless Cellular Paging Private mobile Figure 1. European market of personal communication systems (source : Elsevier Advanced Technology). The design of these chips is subject to stringent requirements in terms of processing performance and power dissipation. At the same

In this paper, we present an efficient exploration algorithm for architecture/compiler co-designs of application-specific instruction-set processors. The huge design space is spanned by processor architecture parameters as well as different compiler optimization strategies. The objective space is multi-dimensional including conflicting objectives such as hardware cost, execution time and code size. The goal of the presented exploration algorithm is to determine the set of Pareto-optimal designs and compiler settings for a given benchmark program. In a case study, while exploring Pareto-optimal designs for a given DSP benchmark program, we show that for a realistic architecture family, the huge search space may be reduced dramatically using proper techniques to prune search spaces that may not contain Pareto-optimal solutions. Finally, we analyse and present solutions on what is the best architecture for a mixture of benchmark programs, i.e., what are the best architecture/compiler co-designs to execute the DSPstone benchmark.

To identify the best processor designs, designers explore a vast design space. To assess the quality of candidate designs, designers construct and use simulators. Unfortunately, simulator construction is a bottleneck in this design-space exploration because existing simulator construction methodologies lead to long simulator development times. This bottleneck limits exploration to a small set of designs, potentially diminishing quality of the final design.

Abstract — Given the recent wave of innovation and diversification in digital signal processor (DSP) architecture, the need for quickly evaluating the true potential of considered architectural choices for a given application has been rising. We propose a new scheme, called Retargetable Estimation, that involves analysis of a high-level description of a DSP application, with aggressive optimization search, to provide a performance estimate of its optimal implementation on the architectures considered. With this scheme, we present a new parameterized architecture model that allows quick retargeting to a wide range of architectural choices, and that emphasizes capturing an architecture's salient optimizing features. We show that for a set of DSP benchmarks and two full applications, hand-optimized performance can be predicted reliably. We applied this scheme to two different processors. I.