Computer Engineering and Applications ›› 2022, Vol. 58 ›› Issue (4): 73-82.DOI: 10.3778/j.issn.1002-8331.2102-0051

• Theory, Research and Development • Previous Articles     Next Articles

Temporal Semantic Programming Language of LET Model

WU Hao, ZHANG Bo, CHEN Xianglan, WANG Chao, LI Xi   

  1. School of Computer Science and Technology, University of Science and Technology of China, Hefei 230026, China
  • Online:2022-02-15 Published:2022-02-15



  1. 中国科学技术大学 计算机科学与技术学院,合肥 230026

Abstract: The correctness of embedded real-time system not only depends on the correctness of the calculation result, but also depends on the correctness of the time to produce the result. However, the uncertain concurrent execution of software brings the problem of unpredictable system time behavior, which increases the verification complexity and costs. Therefore, many real-time programming languages are proposed to improve the time predictability of the system in the field of real-time systems. LET(logical execution time) model combines the advantages of synchronous model ZET(zero execution time) and asynchronous model BET(bounded execution time), and has strong predictability for time. However, the existing real-time programming languages using LET model lack the implementation based on high-level general language. Therefore, a real-time programming language based on LET model—TBC is proposed. This language extends the syntax structure with time semantics based on C, which makes C language have the ability to express time semantics, and analyzes the time semantics through the unique compilation technology, so that TBC can be converted to the instruction set TTI with time operation.

Key words: embedded real-time system, programming language, logical execution time(LET), compiler

摘要: 嵌入式实时系统的正确性不仅取决于计算结果的正确性,更取决于产生结果时间的正确性。然而软件不确定的并发执行带来系统时间行为不可预测问题,使得验证复杂度升高,成本增加,为此实时系统领域提出了许多实时编程语言来提高系统的时间可预测性。LET(logical execution time)模型结合了同步模型ZET(zero execution time)和异步模型BET(bounded execution time)的优点,对时间具有很强的可预测性,但现有采用LET模型的实时编程语言,缺少基于高级通用语言的实现,故提出一种基于LET模型的实时编程语言——TBC。该语言基于C扩展了具有时间语义的语法结构,使得C语言本身具有表示时间语义的能力,并通过独特的编译技术对时间语义进行分析处理,将TBC转换为具有时间操作的指令集TTI。

关键词: 嵌入式实时系统, 编程语言, 逻辑执行时间模型(LET), 编译器