International Business Machines Corporation

Freescale Semiconductor,inc.

Edward L Swarthout

Soummya Mallick

Robert Greg McDonald

James Allan Kahle

Jayanta Bhadra

Mrinal Bose

Hillel Miller

Ekaterina A Trofimova

A test system collects passing event data and failing event data, and merges the collected data into passing subsequences and failing subsequences, respectively. The test system identifies an overlap area between the passing subsequence and the failing subsequence in regards to time slices and tracepoint slices, and creates passing transactions and failing transactions using the event data corresponding to the overlap area. Next, the test system detects a timing discrepancy between the first passing transaction relative to the second passing transaction compared with the first failing transaction relative to the second failing transaction. The test system then reports the detected timing discrepancy, which allows a test engineer to perturb the test program in order to more frequently catch intermittent failures caused by asynchronous timing conditions.

Trace reconstruction for silicon validation of asynchronous systems-on-chip

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.

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

A processor and method of executing a program within a processor are provided. According to the method, a plurality of program instructions comprising a program and a set of auxiliary instructions are stored. An instruction stream including selected ones of the plurality of program instructions is supplied to the processor. In response to the processor processing a program instruction within the instruction stream that has an associated auxiliary instruction within the set of auxiliary instructions, the associated auxiliary instruction is automatically inserted within the instruction stream and the associated auxiliary instruction is executed within the processor.

Processor and method for dynamically inserting auxiliary instructions

A method and system are provided for constructing a program executable by a processor including one or more processing elements for executing threads and a thread scheduler for assigning threads to the processing elements for execution. According to the method, a plurality of threads are provided that each include at least one control flow instruction. From one or more control flow instructions within the plurality of threads, a condition upon which execution of a particular thread depends is determined. In response to the determination, at least one navigation instruction executable by the thread scheduler is created that indicates that the particular thread is to be assigned to one of the processing elements for execution in response to the condition.

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Austin, TX, United States of America

Edward L Swarthout