{"title":"Code compression for VLIW processors using variable-to-fixed coding","authors":"H. Lekatsas, W. Wolf, Yuan Xie","doi":"10.1145/581199.581231","DOIUrl":"https://doi.org/10.1145/581199.581231","url":null,"abstract":"Memory has been one of the most restricted resources in the embedded computing system domain. Code compression has been proposed as a solution to this problem. Previous work used fixed-to-variable coding algorithms that translate fixed-length bit sequences into variable-length bit sequences. In this paper, we propose code compression schemes that use variable-to-fixed (V2F) length coding. We also propose an instruction bus encoding scheme, which can effectively reduce the bus power consumption. Though the code compression algorithm can be applied to any embedded processor, it favors VLIW architectures because VLIW architectures require a high-bandwidth instruction pre-fetch mechanism to supply multiple operations per cycle. Experiments show that the compression ratios using memoryless V2F coding for IA-64 and TMS320C6x are around 72.7% and 82.5% respectively. Markov V2F coding can achieve better compression ratio up to 56% and 70% for IA-64 and TMS320C6x respectively. A greedy algorithm for codeword assignment can reduce the bus power consumption and the reduction depends on the probability model used.","PeriodicalId":413693,"journal":{"name":"15th International Symposium on System Synthesis, 2002.","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129762133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A visual approach to validating system level designs","authors":"Jürgen Ruf, T. Kropf, Jochen Klose","doi":"10.1145/581199.581240","DOIUrl":"https://doi.org/10.1145/581199.581240","url":null,"abstract":"This paper proposes a simulation-based methodology for validation of a system under design in an early phase of development. The key element of this approach is the visual specification, as Live Sequence Charts (LSCs), of the properties to be checked. The LSCs are automatically translated into the input format for the SystemC-based checker engine, which indicates during simulation, if the property is fulfilled or produces a counter-example, if the property is violated. The entire process from the visual property specification to the checking is largely automated, which makes our approach accessible even for users which have not been trained in formal methods.","PeriodicalId":413693,"journal":{"name":"15th International Symposium on System Synthesis, 2002.","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125474246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
W. Fornaciari, V. Trianni, C. Brandolese, D. Sciuto, F. Salice, G. Beltrame
{"title":"Modeling assembly instruction timing in superscalar architectures","authors":"W. Fornaciari, V. Trianni, C. Brandolese, D. Sciuto, F. Salice, G. Beltrame","doi":"10.1145/581199.581230","DOIUrl":"https://doi.org/10.1145/581199.581230","url":null,"abstract":"This paper proposes an original model of the execution time of assembly instructions in superscalar architectures. The approach is based on a rigorous mathematical model and provides a methodology and a toolset to perform data analysis and model tuning. The methodology also provides a framework for building new trace simulators for generic architectures. The results obtained show a good accuracy paired with a satisfactory computational efficiency.","PeriodicalId":413693,"journal":{"name":"15th International Symposium on System Synthesis, 2002.","volume":"519 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134110693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Securing wireless data: system architecture challenges","authors":"A. Raghunathan, N. R. Potlapally, S. Ravi","doi":"10.1145/581199.581243","DOIUrl":"https://doi.org/10.1145/581199.581243","url":null,"abstract":"Security is critical to a wide range of current and future wireless data applications and services. This paper highlights the challenges posed by the need for security during system architecture design for wireless handsets, and provides an overview of emerging techniques to address them. We focus on the computational requirements for securing wireless data transactions, revealing a gap between these requirements and the trends in processing capabilities of embedded processors used in wireless handsets. We also demonstrate that the use of security protocols causes significant degradation in battery life, a problem that will worsen due to the slow growth in battery capacities. These trends point to a wireless security processing gap that, unless addressed, will impede the deployment of secure high-speed wireless data and multi-media applications. We discuss approaches that are currently being pursued to bridge this gap, including low-complexity cryptographic algorithms, security enhancements to embedded processors, and advanced system architectures for wireless handsets that are enabled by new system level design methodologies.","PeriodicalId":413693,"journal":{"name":"15th International Symposium on System Synthesis, 2002.","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125430561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Nicolau, N. Dutt, Aviral Shrivastava, P. Biswas, A. Halambi
{"title":"A design space exploration framework for reduced bit-width Instruction Set architecture (rISA) design","authors":"A. Nicolau, N. Dutt, Aviral Shrivastava, P. Biswas, A. Halambi","doi":"10.1145/581199.581228","DOIUrl":"https://doi.org/10.1145/581199.581228","url":null,"abstract":"Code size is a critical concern in many embedded system applications, especially those using RISC cores. One promising approach for reducing code size is to employ a \"dual instruction set\", where processor architectures support a normal (usually 32 bit) Instruction Set, and a narrow, space-efficient (usually 16 bit) Instruction Set with a limited set of opcodes and access to a limited set of registers. This feature (termed rISA) can potentially reduce the code size by up to 50% with minimal performance degradation. However, contemporary processors incorporate only a simple rISA feature with severe restrictions on register accessibility. We present a compiler-in-the-loop Design Space Exploration framework that is capable of exploring various interesting rISA designs. We also present experimental results using this framework and show rISA designs that improve on the code size reduction obtained by existing rISA architectures.","PeriodicalId":413693,"journal":{"name":"15th International Symposium on System Synthesis, 2002.","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116075801","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Data memory design considering effective bitwidth for low-energy embedded systems","authors":"H. Yasuura, H. Tomiyama, T. Okuma, Yun Cao","doi":"10.1145/581199.581245","DOIUrl":"https://doi.org/10.1145/581199.581245","url":null,"abstract":"This paper presents a novel low-energy memory design technique, considering effective bitwidth of variables for application-specific systems, called VAbM technique. It targets the exploitation of both data locality and effective bitwidth of variables to reduce energy consumed by redundant bits. Under constraints of the number of memory banks, the VAbM technique uses variable analysis results to perform allocating and assigning on-chip RAM into multiple memory banks, which have different size with different number of word lines and different number of bit lines tailored to each application requirements. Experimental results with several real embedded applications demonstrate significant energy reduction up to 64.8% over monolithic memory, and 18.4% over memory designed by banking technique.","PeriodicalId":413693,"journal":{"name":"15th International Symposium on System Synthesis, 2002.","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126670162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"An adaptive low-power transmission scheme for on-chip networks","authors":"P. Ienne, Patrick Thiran, G. Micheli, F. Worm","doi":"10.1145/581199.581221","DOIUrl":"https://doi.org/10.1145/581199.581221","url":null,"abstract":"Systems-on- Chip (SoC) are evolving toward complex heterogeneous multiprocessors made of many predesigned macrocells or subsystems with application-specific interconnections. Intra-chip interconnects are thus becoming one of the central elements of SoC design and pose conflicting goals in terms of low energy per transmitted bit, guaranteed signal integrity, and ease of design. This work introduces and shows first results on a novel interconnect system which uses low-swing signalling, error detection codes, and a retransmission scheme; it minimises the interconnect voltage swing and frequency subject to workload requirements and S/N conditions. Simulation results show that tangible savings in energy can be attained while achieving at the same time more robustness to large variations in actual workload, noise, and technology quality (all quantities easily mispredicted in very complex systems and advanced technologies). It can be argued that traditional worst-case correct-by-design paradigm will be less and less applicable in future multibillion transistor SoC and deep sub-micron technologies; this work represents a first example towards robust adaptive designs.","PeriodicalId":413693,"journal":{"name":"15th International Symposium on System Synthesis, 2002.","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130711759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Controller estimation for FPGA target architectures during high-level synthesis","authors":"O. Bringmann, W. Rosenstiel, C. Menn","doi":"10.1145/581199.581213","DOIUrl":"https://doi.org/10.1145/581199.581213","url":null,"abstract":"In existing synthesis systems, the influence of the area and delay of the controller is not or not sufficiently taken into account. But the controller can have a big influence, especially, if a certain data-path realization requires a huge number of states and/or control signals. This paper presents a new approach on controller estimation during high-level synthesis for FPGA-based target architectures. The estimator, presented in this paper can be invoked after or during every synthesis-step, i.e. allocation, scheduling and binding, respectively. By considering the controller influence on the overall area of a design, design space exploration can be made more accurate and less error prone. We present an approach for estimating area of the controller based on information which are easily accessible during each step of highlevel synthesis, so no explicit description of the controller, which usually will be generated after the binding, is necessary. This is particularly valuable in the allocation phase, where intensive design space explorations have to be done, based on fast and accurate estimates.","PeriodicalId":413693,"journal":{"name":"15th International Symposium on System Synthesis, 2002.","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132945277","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The formal execution semantics of SpecC","authors":"R. Dömer, A. Gerstlauer, W. Müller","doi":"10.1145/581199.581234","DOIUrl":"https://doi.org/10.1145/581199.581234","url":null,"abstract":"We present a rigorous but transparent semantics definition of the SpecC language that covers the execution of SpecC behaviors and their interaction with the kernel process. The semantics include wait, wait for, par, and try statements as they are introduced in SpecC. We present our definition in form of distributed abstract state machine (ASM) rules strictly following the lines of the SpecC Language Reference Manual. We mainly see our formal semantics in three application areas. First, it is a concise, unambiguous description for documentation and standardization. Second, it applies as a high-level, pseudo code-oriented specification for the implementation of a SpecC simulator. Finally, it is a first step for SpecC synthesis in order to identify similar concepts with other languages like VHDL and SystemC for the definition of common patterns and language subsets.","PeriodicalId":413693,"journal":{"name":"15th International Symposium on System Synthesis, 2002.","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130581821","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"An accelerated datapath width optimization scheme for area reduction of embedded systems","authors":"H. Yasuura, Yun Cao, M. Uddin","doi":"10.1145/581199.581208","DOIUrl":"https://doi.org/10.1145/581199.581208","url":null,"abstract":"Datapath width optimization is very effective for reducing the area of a custom-made embedded system. The trivial way of optimization is to iteratively customize, evaluate, and redesign a system to reach near an optimal value. The resulting effect is a long design time. In this paper, we introduce an effective scheme that accelerates design. A system-level pruning of design exploration space speeds up the optimization process. Through a single-pass simulation for a reference customization and a model for estimating and evaluating the system's performance, pruning of design space is achieved. Experimental results show that a substantial reduction in design time is possible.","PeriodicalId":413693,"journal":{"name":"15th International Symposium on System Synthesis, 2002.","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116029129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}