Method and system for executing a program within a multiscalar processor by processing linked thread descriptors

A multiscalar processor and method of executing a multiscalar program within a multiscalar processor having a plurality of processing elements and a thread scheduler are provided. The multiscalar program includes a plurality of threads that are each composed of one or more instructions of a selected instruction set architecture. Each of the plurality of threads has a single entry point and a plurality of possible exit points. The multiscalar program further comprises thread code including a plurality of data structures that are each associated with a respective one of the plurality of threads. According to the method, a third data structure among the plurality of data structures is supplied to the thread scheduler. The third data structure, which is associated with a third thread among the plurality of threads, specifies a first data structure associated with a first possible exit point of the third thread and a second data structure associated with a second possible exit point of the third thread. The third thread is assigned to a selected one of the plurality of processing elements for execution. Prior to completing execution of the third thread, the thread scheduler selects from among the first and the second possible exit points of the third thread. In response to the selection, a corresponding one of the first and second data structures is loaded into the thread scheduler for processing.