公开(公告)号：US6081665A

公开(公告)日：2000-06-27

申请号：US994393

申请日：1997-12-19

申请人： Kelvin D. Nilsen ,  Simanta Mitra ,  Steven J. Lee

发明人： Kelvin D. Nilsen ,  Simanta Mitra ,  Steven J. Lee

IPC分类号： G06F9/40 ,  G06F9/455 ,  G06F12/02 ,  G06F9/45

CPC分类号： G06F9/45504 ,  G06F12/0269 ,  G06F9/4428 ,  G06F2212/702

摘要： The invention is a method for use in executing portable virtual machine computer programs under real-time constraints. The invention includes a method for implementing a single abstract virtual machine execution stack with multiple independent stacks in order to improve the efficiency of distinguishing memory pointers from non-pointers. Further, the invention includes a method for rewriting certain of the virtual machine instructions into a new instruction set that more efficiently manipulates the multiple stacks. Additionally, using the multiple-stack technique to identify pointers on the run-time stack, the invention includes a method for performing efficient defragmenting real-time garbage collection using a mostly stationary technique. The invention also includes a method for efficiently mixing a combination of byte-code, native, and JIT-translated methods in the implementation of a particular task, where byte-code methods are represented in the instruction set of the virtual machine, native methods are written in a language like C and represented by native machine code, and JIT-translated methods result from automatic translation of byte-code methods into the native machine code of the host machine. Also included in the invention is a method to implement a real-time task dispatcher that supports arbitrary numbers of real-time task priorities given an underlying real-time operating system that supports at least three task priority levels. Finally, the invention includes a method to analyze and preconfigure virtual memory programs so that they can be stored in ROM memory prior to program.

摘要翻译： 本发明是用于在实时限制下执行便携式虚拟机计算机程序的方法。 本发明包括一种用于实现具有多个独立堆栈的单个抽象虚拟机执行堆栈的方法，以便提高区分存储器指针与非指针的效率。 此外，本发明包括一种用于将某些虚拟机指令重写成更有效地操纵多个堆栈的新指令集的方法。 另外，使用多栈技术来识别运行时堆栈上的指针，本发明包括一种使用大多数固定技术来执行有效的碎片整理实时垃圾收集的方法。 本发明还包括一种用于在特定任务的实现中有效地混合字节码，本地和JIT转换的方法的组合的方法，其中字节码方法在虚拟机的指令集中表示，本地方法是 用C语言编写并由本地机器代码表示，并且JIT翻译的方法源自将字节码方法自动转换为主机的本地机器代码。 本发明还包括一种实现实时任务调度器的方法，该实时任务调度器在支持至少三个任务优先级的基础实时操作系统时，支持任意数量的实时任务优先级。 最后，本发明包括分析和预配置虚拟存储器程序的方法，使得它们可以在程序之前存储在ROM存储器中。