Patents by Inventor Cristiano L. Pereira

Cristiano L. Pereira has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20140189256
    Abstract: A processor includes a first core to execute a first software thread, a second core to execute a second software thread, and shared memory access monitoring and recording logic. The logic includes memory access monitor logic to monitor accesses to memory by the first thread, record memory addresses of the monitored accesses, and detect data races involving the recorded memory addresses with other threads. The logic includes chunk generation logic is to generate chunks to represent committed execution of the first thread. Each of the chunks is to include a number of instructions of the first thread executed and committed and a time stamp. The chunk generation logic is to stop generation of a current chunk in response to detection of a data race by the memory access monitor logic. A chunk buffer is to temporarily store chunks until the chunks are transferred out of the processor.
    Type: Application
    Filed: December 28, 2012
    Publication date: July 3, 2014
    Inventors: TIM KRANICH, GILLES A. POKAM, JUSTIN E. GOTTSCHLICH, KLAUS DANNE, ROLF KASSA, SHILIANG HU, CRISTIANO L. PEREIRA
  • Publication number: 20140089642
    Abstract: One or more embodiments may provide a method for performing a replay. The method includes initiating execution of a program, the program having a plurality of sets of instructions, and each set of instructions has a number of chunks of instructions. The method also includes intercepting, by a virtual machine unit executing on a processor, an instruction of a chunk of the number of chunks before execution. The method further includes determining, by a replay module executing on the processor, whether the chunk is an active chunk, and responsive to the chunk being the active chunk, executing the instruction.
    Type: Application
    Filed: September 27, 2012
    Publication date: March 27, 2014
    Inventors: Justin E. Gottschlich, Klaus Danne, Cristiano L. Pereira, Gilles A. Pokam, Rolf Kassa, Shiliang Hu, Tim Kranich
  • Publication number: 20140007054
    Abstract: Methods and systems to identify and reproduce concurrency bugs in multi-threaded programs are disclosed. An example method disclosed herein includes defining a data type. The data type includes a first predicate associated with a first thread of a multi-threaded program that is associated with a first condition, a second predicate that is associated with a second thread of the multi-threaded program, the second predicate being associated with a second condition, and an expression that defines a relationship between the first predicate and the second predicate. The relationship, when satisfied, causes the concurrency bug to be detected. A concurrency bug detector conforming to the data type is used to detect the concurrency bug in the multi-threaded program.
    Type: Application
    Filed: June 27, 2012
    Publication date: January 2, 2014
    Inventors: Youfeng Wu, Justin E. Gottschlich, Gilles Pokam, Shiliang Hu, Ali-Reza Adl-Tabatabai, Cristiano L. Pereira
  • Publication number: 20130297978
    Abstract: A method and system for detecting abnormal interleavings in a multi-threaded program includes generating an execution log in response to execution of the multi-threaded program. Based on the execution log, a list of allowable immediate interleavings is generated if the execution of the multi-threaded program resulted in no concurrency errors and a list of suspicious immediate interleavings is generated if the execution of the multi-threaded program resulted in one or more concurrency errors. The first and second lists are compared to generate a list of error-causing immediate interleavings. A replayable core is then generated and executed based on the list of error-causing immediate interleavings.
    Type: Application
    Filed: September 29, 2011
    Publication date: November 7, 2013
    Inventors: Nicholas A. Jalbert, Cristiano L. Pereira, Gilles A. Pokam