CPA-CPL: A hardware-design inspired methodology for parallel programming

并行编程的一个弱点是缺乏组合性；独立编写的并行程序，例如库和包，不能组合在一起产生具有可预测的性能或功能的大型并行程序。一个人可能拥有FFT和线性方程解算器的最佳并行实现，然而并行调用这两个过程的大型并行程序可能运行不好。对于那些本质上是并行的但通过组合现有的顺序实现而产生的应用程序来说，这个问题要严重得多。想想你的手机：它可能会在你上网时挂断来电，或者在你接听电话时不会停止播放音乐。问题在于组合--两个独立编写的程序在并行环境中不能正确交互。软件组合的可扩展模型是空间多路复用，其中一组资源(例如，处理器和内存)专门用于执行给定的程序片段或模块。这项研究计划定义和使用Bluesoft--Bluespec SystemVerilog(BSV)的派生语言--作为其源语言。Bluespec？S的语义很好理解，在学术界和工业界都有使用它进行硬件设计的丰富经验。Bluesoft为Bluespec增加了一个？顺序连接词？用于组合原子动作，这是软件设计所需的关键功能。Bluesoft编译器将结合用于编译Bluespec和StreamIt的策略，StreamIt是麻省理工学院为平铺架构开发的基于流的语言。Bluesoft编译器将借用BSV编译器的静态精化阶段来生成模块网络，并将StreamIt编译器中使用的复杂程序分析和代码生成技术用于后端。

A source of weakness in parallel programming has been the lack of compositionality; independently-written parallel programs, e.g., libraries and packages, can't be combined to produce large parallel programs with predictable performance or functionality. One may have the best parallel implementations of FFT and Linear Equation Solvers and yet a large parallel program that calls both of these procedures in parallel may not run well. The problem is much worse for applications that are inherently parallel but produced by combining existing sequential implementations. Consider your cell phone: it may drop an incoming call while you are surfing the web, or not stop playing the music when you answer a call. The problem is compositionally -- two independently written programs don't interact properly in a parallel setting.A scalable model for software composition is space-multiplexing, where a set of resources (e.g., processors and memory) are devoted exclusively to executing a given program fragment or module. This research plans to define and use Bluesoft -- a derivative of the Bluespec SystemVerilog (BSV) -- as its source language. Bluespec?s semantics are well understood and there is substantial experience in using it for hardware design in both academia and industry. Bluesoft adds to Bluespec a ?sequential connective? for combining atomic actions, a crucial feature needed for software design. The Bluesoft compiler will combine the strategies used for compiling Bluespec and StreamIt, a stream-based language developed at MIT for tiled architectures. The Bluesoft compiler will borrow the static elaboration phase of the BSV compiler to generate a network of modules and use the sophisticated program analysis and code generation techniques used in the StreamIt compiler for the backend.