Memory Management Scheme Based on the Quasi-Linear Type System

本研究计划的目的是建立一个新的计划，内存管理的基础上准线性类型的系统，小林已提出。利用准线性类型系统，我们可以在编译时找到对每个堆数据的最后一次访问，并插入一条释放指令，从而构造一个更高效、更安全的内存管理系统。主要研究结果如下：基于准线性类型系统的内存分配/释放指令的插入我们设计了一个基于准线性类型系统的算法，用于寻找每个堆数据的最后一个访问点并插入分配/释放指令。我们将其纳入一个函数式编程语言ML.设计和实现的字节码语言为我们的内存管理方案我们设计和实现了一个字节码语言，这是适合我们的内存管理方案基于准线性类型系统.与垃圾收集集成由于不是所有的堆数据可以维护我们的内存管理方案，与传统的内存管理方案（GC）的集成是必要的。主要问题是如何改进多处理器上的GC以及如何处理由我们的内存管理方案产生的悬挂指针。我们处理这些问题，并建立了一种方法来整合这两种方案的内存管理。资源使用分析我们推广了准线性类型系统，并构造了一个类型系统，不仅检查使用的内存，而且还检查其他资源，如文件，网络等。

The aim of this research project was to establish a new scheme for memory management based on the quasi-linear type system which Kobayashi has proposed. With the quasi-linear type system, we can find the last access to each heap data and insert an instruction for deallocation at compile-time, by which we can construct a more efficient, safe memory management system. Main results are summarized as follows.Insertion of memory allocation/deallocation instructions based on the quasi-linear type systemWe devised an algorithm for finding the last access point for each heap data and inserting allocation/deallocation instructions, based on the quasi-linear type system. We incorporated it into a functional programming language ML.Design and implementation of a bytecode language for our memory management schemeWe designed and implemented a bytecode language that is suitable for our memory management scheme based on the quasi-linear type system.Integration with garbage collectionSince not all heap data can be maintained by our memory management scheme, integration with conventional memory management schemes (GC) is necessary. The main issues are how to improve GC on multiprocessors and how to deal with dangling pointers produced by our memory management scheme. We dealt with these issues and established a method to integrate the two schemes for memory management.Resource usage analysisWe generalized the quasi-linear type system and constructed a type system for checking usage of not only the memory but also other resources such as files, networks, etc.