Runtime Binary Re-Compilation for Enterprise-Scale Computing

在不久的将来，一个更大的一套指标，以监测程序的行为将更容易获得，预计将成为可用的一些计算机体系结构。这种发展导致了在运行时使用这些指标来更改正在执行的代码以提高性能的可能性。实现这一愿景所需的一些开发包括：（1）重新关注硬件运行时工具框架的控制机制;（2）具有成本效益的数据表示和简化框架，必须解决收集的信息量与收集和分析的计算成本之间的权衡;以及（3）一组基于路径专门化的新代码转换。 另一方面，计算机系统的硬件随着每一代处理器提供的新特征而快速发展。此外，编译器研究人员和开发人员开发了新的和更积极的编译策略。一个长期存在的问题是，许多新的硬件功能只能在编译器在生成可执行二进制文件时知道它们的情况下才能访问。此外，除非应用程序使用较新的编译器进行编译，否则无法部署任何改进的编译策略。然而，许多重要的软件应用程序运行相同的二进制文件多年-或者更有可能从未重新编译-因此它们无法访问硬件提供的更新功能，也无法从更高级的编译策略中受益。这个建议的目标是开发一个运行时二进制重新编译框架，以解决这个问题，允许新生成的二进制文件访问最新的硬件功能和编译器技术。

In the near future a larger set of metrics to monitor program behaviour will be much more easily accessible are expected to become available in some computer architectures. This development leads to the possibility of using such metrics at runtime to change the code being executed to improve performance. Some of the developments that will be necessary to realize this vision include (1) a control mechanism to re-focus the hardware runtime instrumentation framework; (2) a cost-effective data representation and reduction framework that will have to resolve trade-offs between the amount of information gathered and the computational cost of the gathering and analysis; and (3) a set of new code transformations based on path specialization. On the other hand, the hardware of computer systems rapidly evolves with new features offered with each processor generation. Also, new and more aggressive compilation strategies are developed by compiler researchers and developers. A long-standing problem is that many of the new hardware features can only be accessed if the compiler is aware of them at the time that it generates executable binaries. Moreover, none of the improved compilation strategies can be deployed unless the application is compiled with the newer compiler. However, many important software applications run the same binaries for many years --- or more likely are never re-compiled --- and therefore they do not access the newer features that the hardware makes available and do not benefit from more advanced compilation strategies. The goal of this proposal is to develop a run-time binary recompilation framework to solve this problem by allowing the newly generated binaries to access the most recent hardware features and compiler techniques.