关键词：精密定时；定时设计；电子物理系统（CPS）；ISA；硬件；软件
摘 要：Cyber-Physical Systems (CPS) are integrations of computation with physical processes. These systems must be equipped to handle the inherent concurrency and inexorable passage of time of physical processes. Traditional computing abstractions only concern themselves with the functional aspects of a program, and not its timing properties.In this work, we address the difficulties of handling time in computing systems by reexamining the lower levels of abstraction. In particular, we focus on the instruction set architecture (ISA) layer and its affects on microarchitecture design. The ISA defines the contract between software instructions and hardware implementations. Modern ISAs do not constrain timing properties of instructions as part of the contract. Thus, architecture designs have largely implemented techniques that improve average performance at the expense of execution time variability. This leads to imprecise WCET bounds that limit the timing predictability and timing composability of architectures.