High-level synthesis - also called behavioral and architectural-level synthesis - is a key design technology to realize systems on chip/package of various kinds, whether single or multi-processors, homogeneousor heterogeneous,for the emb- ded systems market or not. Actually, as technology progresses and systems become increasingly complex, the use of high-level abstractions and synthesis methods becomes more and more a necessity. Indeed, the productivityof designers increases with the abstraction level, as demonstrated by practices in both the software and hardware domains. The use of high-level models allows designers with systems, rather than circuit, backgroundto be productive,thus matching the trend of industry whichisdeliveringanincreasinglylargernumberofintegratedsystemsascompared to integrated circuits. The potentials of high-level synthesis relate to leaving implementation details to the design algorithms and tools, including the ability to determine the precise timing of operations, data transfers, and storage. High-level optimization, coupled with high-levelsynthesis, canprovidedesignerswith the optimalconcurrencystr- ture for a data ow and corresponding technological constraints, thus providing the balancing act in the trade-offbetween latency and resource usage. For complex s- tems, the design space exploration,i.e., the systematic search for the Pareto-optimal points, can only be done by automated high-level synthesis and optimization tools. Nevertheless, high-level synthesis has been showing a long gestation period. Despite early resultsin the 1980s,it is still not commonpracticein hardwaredesign.
