Model-driven development of pipelined systems

流水线是一种广泛应用于数字硬件系统的性能优化，用于从简单的信号处理滤波器到高性能微处理器的系统中。流水线通过重叠执行多个指令来提高性能，类似于多辆汽车在汽车装配线上流动的方式。尽管将管道视为框图是直观的，但它很难设计和验证，因为流经管道的指令之间的交互可能会产生微妙的错误。本研究的目标是通过为流水线系统的模型驱动开发创建理论、工具和技术来减少开发工作量并提高数字硬件系统的质量。模型驱动的开发是一种开发风格，它关注系统的模型，而不仅仅是最终的实现。模型驱动的开发区分了单个系统的模型和为整个系统类建模的元模型。元模型捕获类中所有系统共有的特征，并识别系统之间的变异点。我们每天都在使用元模型，而不会被我们思维的元级本质所负担，甚至不会意识到我们正在使用一个模型。道路地图上的地图符号惯例就是一个例子：所有区域都以相同的比例绘制，水是蓝色的，更粗的线意味着更大的道路，等等。这些约定是地图的元模型，而单个地图是特定地理区域的模型。我们将创建一组元模型来描述管道系统的一般行为和管道的特定性能优化。我们将在CAD工具中对这些元模型进行编码，这将使工程师能够重用高级设计策略，并将设计系统的过程与实现设计的过程清晰地分离开来。这项研究将通过减少犯错的机会和更容易发现新的性能优化的机会来提高设计质量。

Pipelining is a widely used performance optimization for digital-hardware systems that is used in systems ranging from simple signal-processing filters to high-performance microprocessors. Pipelining increases performance by overlapping the execution of multiple instructions, analogous to the way that multiple cars flow through an automobile assembly line. Although intuitive when viewed as block diagrams, pipelines are difficult to design and verify, because subtle bugs can arise from the interactions between instructions flowing through the pipeline. The goal of this research is to reduce the development effort and improve the quality of digital-hardware systems by creating theories, tools, and techniques for the model-driven development of pipelined systems. Model-driven development is a style of development that focusses on models of a system, rather than just the final implementation. Model-driven development distinguishes between a model of an individual system and a metamodel that models an entire class of systems. A metamodel captures features that are common to all systems in the class and identifies points of variation between systems. We make daily use of metamodels without being burdened by the meta-level nature of our thinking, or even being aware that we are using a model. Conventions for cartographic symbols on road maps are an example: all areas are drawn at the same scale, water is blue, thicker lines mean larger roads, etc. These conventions are a metamodel for maps, and an individual map is a model for a specific geographical area. We will create a family of metamodels that describe the behaviour of pipelined systems in general and of specific performance optimizations for pipelines. We will encode these metamodels in CAD tools that will enable engineers to reuse high-level design strategies and cleanly separate the process of designing a system from that of implementing the design. The research will improve design quality by reducing the opportunities to make mistakes and making it easier to discover opportunities for new performance optimizations.