Patents by Inventor Gavin B. Meil

Gavin B. Meil 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).

  • Patent number: 9916407
    Abstract: A design tool can implement phase algebra based design evaluation to evaluate a circuit design with a compact representation of waveforms without simulating the individual waveforms. The tool can determine whether module instances of a register level circuit design share a common usage, each instance being associated with a mapping. Two instances share a common usage if a sequence of signal transition representations received by the first instance can be mapped using a first mapping to the same common sequence of signal transition representations as a mapping of another sequence of signal transition representations received by the second instance using a second mapping. A result sequence of signal transition representations was generated by a previous propagation of the common sequence through the common usage. If the two instances share the common usage, the result sequence is mapped to an output sequence for the second instance using the second mapping.
    Type: Grant
    Filed: February 25, 2015
    Date of Patent: March 13, 2018
    Assignee: International Business Machines Corporation
    Inventors: Gabor Drasny, Gavin B. Meil
  • Publication number: 20170364620
    Abstract: Integrated circuits (ICs) rely on static timing analysis during their design to ensure that they will operate at desired frequencies. Delays between sequential elements (e.g., latches and flip-flops) are constrained to meet target clock periods. Certain signals, however, such as untimed nets may be excluded from timing constraints if the circuit function does not require these nets to switch and propagate to sequential elements within the clock period. However, a signal marked as “untimed” may have been mistakenly specified by the designer as an untimed net. To verify that an untimed net does not negatively impact the function of the design logic, the embodiments herein generate upstream and downstream event networks using shadow logic that corresponds to design logic upstream and downstream of the untimed net. A metastability network coupled to these networks is used to model nondeterminism and metastability resulting from transitions or potential glitches on the untimed net.
    Type: Application
    Filed: June 15, 2016
    Publication date: December 21, 2017
    Inventor: Gavin B. Meil
  • Patent number: 9830412
    Abstract: A design tool can implement phase algebra based design evaluation to evaluate a circuit design with a compact representation of numerous waveforms without simulating the individual waveforms. The design tool can determine an input sequence of signal transition representations associated with an input net of a component in a register transfer level circuit design, where each signal transition representation represents a nondeterministic transition from a previous signal state to one or more possible signal states. Determining the input sequence of signal transition representations includes determining that a subsequence of the input sequence of signal transition representations indicates at most one transition within the subsequence of the input sequence.
    Type: Grant
    Filed: November 19, 2014
    Date of Patent: November 28, 2017
    Assignee: International Business Machines Corporation
    Inventors: Gabor Drasny, Gavin B. Meil
  • Patent number: 9798844
    Abstract: A design tool can implement phase algebra based design evaluation to evaluate a circuit design with a compact representation of waveforms without simulating the individual waveforms. The tool can determine whether module instances of a register level circuit design share a common usage, each instance being associated with a mapping. Two instances share a common usage if a sequence of signal transition representations received by the first instance can be mapped using a first mapping to the same common sequence of signal transition representations as a mapping of another sequence of signal transition representations received by the second instance using a second mapping. A result sequence of signal transition representations was generated by a previous propagation of the common sequence through the common usage. If the two instances share the common usage, the result sequence is mapped to an output sequence for the second instance using the second mapping.
    Type: Grant
    Filed: June 9, 2015
    Date of Patent: October 24, 2017
    Assignee: International Business Machines Corporation
    Inventors: Gabor Drasny, Gavin B. Meil
  • Patent number: 9547732
    Abstract: A circuit design checker receives a circuit design. The circuit design can include a first set of one or more logic components in a first clock domain and a second set of one or more logic components in a second clock domain. The clock domain checker identifies a first subset of the second set of one or more logic components that receive one or more asynchronous clock domain crossings. The circuit design is traversed to determine whether a subset of the one or more asynchronous clock domain crossings does not pass through a signal having an attribute indicating that the signal is intended to be part of the one or more asynchronous clock domain crossings. If such a crossing exists, an error is indicated for the circuit design.
    Type: Grant
    Filed: December 4, 2014
    Date of Patent: January 17, 2017
    Assignee: International Business Machines Corporation
    Inventors: Gabor Drasny, Gavin B. Meil
  • Patent number: 9536024
    Abstract: A circuit design checker receives a circuit design. The circuit design can include a first set of one or more logic components in a first clock domain and a second set of one or more logic components in a second clock domain. The clock domain checker identifies a first subset of the second set of one or more logic components that receive one or more asynchronous clock domain crossings. The circuit design is traversed to determine whether a subset of the one or more asynchronous clock domain crossings does not pass through a signal having an attribute indicating that the signal is intended to be part of the one or more asynchronous clock domain crossings. If such a crossing exists, an error is indicated for the circuit design.
    Type: Grant
    Filed: June 9, 2015
    Date of Patent: January 3, 2017
    Assignee: International Business Machines Corporation
    Inventors: Gabor Drasny, Gavin B. Meil
  • Publication number: 20160188760
    Abstract: A design tool can implement phase algebra based design evaluation to evaluate a circuit design with a compact representation of waveforms without simulating the individual waveforms. The tool can determine a first sequence of signal transition representations of a first signal of a first module of a register level circuit design. The second module of the register level circuit design comprises the first module, arranged in a hierarchical order. The tool can determine a second sequence of signal transition representations of the first signal of the first module. The signal transition representations of a second signal are propagated from the second module to the first module using the first signal. The tool can determine whether a first mapping can be determined between the first sequence and the second sequence, where the second sequence is propagated through the first module.
    Type: Application
    Filed: March 4, 2016
    Publication date: June 30, 2016
    Inventors: Gabor Drasny, Gavin B. Meil
  • Publication number: 20160188785
    Abstract: A design tool can implement phase algebra based design evaluation to evaluate a circuit design with a compact representation of waveforms without simulating the individual waveforms. The tool can determine that a first sequence of signal transition representations of a first signal of the first module comprises a null sequence. The first module of a register level circuit design comprises a second module, the first module and the second module arranged in a hierarchical order. The tool can determine a second sequence of signal transition representations of a second signal of the second module. Signal transition representations of the first signal are for propagation from the first module to the second module using the second signal. The tool can extract a non-null sequence for the first sequence based on the second sequence to generate an extracted first sequence.
    Type: Application
    Filed: March 4, 2016
    Publication date: June 30, 2016
    Inventors: Gabor Drasny, Gavin B. Meil
  • Publication number: 20160078162
    Abstract: A design tool can implement phase algebra based design evaluation to evaluate a circuit design with a compact representation of numerous waveforms without simulating the individual waveforms. The design tool can determine two or more input sequences of signal transition representations associated with an input net of an indicated component in an RTL circuit design, where the two or more input sequences of signal transition representations are associated with a mode element. Each signal transition representation represents a nondeterministic transition from a previous signal state to possible signal state(s). The mode element indicates a selection between two or more output sequences of signal transition representations. It is determined, based on the indicated component and the mode element, two or more output sequences of signal transition representations derived from the input sequence(s) of signal transition representations.
    Type: Application
    Filed: August 31, 2015
    Publication date: March 17, 2016
    Inventors: Gabor Drasny, Gavin B. Meil
  • Patent number: 9268889
    Abstract: Various implementations of a method, system and computer program product receive a circuit model that can include an asynchronous crossing between a first set of one or more logic components in a first clock domain and a second set of one or more logic components in a second clock domain. A shadow network can be constructed that corresponds to the asynchronous crossing, where the shadow network includes at least one of an asynchronous transition detector, an asynchronous sample detector, and a metastability timer. The shadow network can include shadow network signals corresponding to signals of the asynchronous crossing.
    Type: Grant
    Filed: May 12, 2014
    Date of Patent: February 23, 2016
    Assignee: International Business Machines Corporation
    Inventor: Gavin B Meil
  • Patent number: 9251304
    Abstract: A design tool can implement phase algebra based design evaluation to efficiently evaluate a circuit design with a compact representation of numerous waveforms without simulating the individual waveforms. Instead of individual waveforms, the phase algebra based design evaluation employs compact representations of a group or set of waveforms. Phase algebra based evaluation constructs representations of a set of waveforms based on relationships among a devised set of functions that account for the various states of a signal over time, including transitions and glitches. A memorized-transition function, referred to herein as an M-function, indicates signal transitions over time.
    Type: Grant
    Filed: July 10, 2014
    Date of Patent: February 2, 2016
    Assignee: International Business Machines Corporation
    Inventors: Gabor Drasny, Gavin B Meil
  • Publication number: 20150370940
    Abstract: A design tool can implement phase algebra based design evaluation to evaluate a circuit design with a compact representation of numerous waveforms without simulating the individual waveforms. The design tool can determine an input sequence of signal transition representations associated with an input net of a component in RTL circuit design, where each signal transition representation represents a nondeterministic transition from a previous signal state to possible signal state(s). Determining the input sequence of signal transition representations includes determining that the input sequence of signal transition representations indicates an input gated clock waveform. The design tool also can determine, based on the indicated component and on the input gated clock waveform, an output sequence of signal transition representations derived from the input sequence of signal transition.
    Type: Application
    Filed: August 31, 2015
    Publication date: December 24, 2015
    Inventors: Gabor Drasny, Gavin B. Meil
  • Publication number: 20150370939
    Abstract: A design tool can implement phase algebra based design evaluation to evaluate a circuit design with a compact representation of numerous waveforms without simulating the individual waveforms. The design tool can determine an input sequence of signal transition representations associated with an input net of a component in a register transfer level circuit design, where each signal transition representation represents a nondeterministic transition from a previous signal state to one or more possible signal states. Determining the input sequence of signal transition representations includes determining that a subsequence of the input sequence of signal transition representations indicates at most one transition within the subsequence of the input sequence.
    Type: Application
    Filed: August 31, 2015
    Publication date: December 24, 2015
    Inventors: Gabor Drasny, Gavin B. Meil
  • Publication number: 20150269299
    Abstract: A design tool can implement phase algebra based design evaluation to evaluate a circuit design with a compact representation of waveforms without simulating the individual waveforms. The tool can determine whether module instances of a register level circuit design share a common usage, each instance being associated with a mapping. Two instances share a common usage if a sequence of signal transition representations received by the first instance can be mapped using a first mapping to the same common sequence of signal transition representations as a mapping of another sequence of signal transition representations received by the second instance using a second mapping. A result sequence of signal transition representations was generated by a previous propagation of the common sequence through the common usage. If the two instances share the common usage, the result sequence is mapped to an output sequence for the second instance using the second mapping.
    Type: Application
    Filed: June 9, 2015
    Publication date: September 24, 2015
    Inventors: Gabor Drasny, Gavin B. Meil
  • Publication number: 20150269296
    Abstract: A circuit design checker receives a circuit design. The circuit design can include a first set of one or more logic components in a first clock domain and a second set of one or more logic components in a second clock domain. The clock domain checker identifies a first subset of the second set of one or more logic components that receive one or more asynchronous clock domain crossings. The circuit design is traversed to determine whether a subset of the one or more asynchronous clock domain crossings does not pass through a signal having an attribute indicating that the signal is intended to be part of the one or more asynchronous clock domain crossings. If such a crossing exists, an error is indicated for the circuit design.
    Type: Application
    Filed: June 9, 2015
    Publication date: September 24, 2015
    Inventors: Gabor Drasny, Gavin B. Meil
  • Publication number: 20150169816
    Abstract: A design tool can implement phase algebra based design evaluation to evaluate a circuit design with a compact representation of waveforms without simulating the individual waveforms. The tool can determine whether module instances of a register level circuit design share a common usage, each instance being associated with a mapping. Two instances share a common usage if a sequence of signal transition representations received by the first instance can be mapped using a first mapping to the same common sequence of signal transition representations as a mapping of another sequence of signal transition representations received by the second instance using a second mapping. A result sequence of signal transition representations was generated by a previous propagation of the common sequence through the common usage. If the two instances share the common usage, the result sequence is mapped to an output sequence for the second instance using the second mapping.
    Type: Application
    Filed: February 25, 2015
    Publication date: June 18, 2015
    Inventors: Gabor Drasny, Gavin B. Meil
  • Publication number: 20150161312
    Abstract: A circuit design checker receives a circuit design. The circuit design can include a first set of one or more logic components in a first clock domain and a second set of one or more logic components in a second clock domain. The clock domain checker identifies a first subset of the second set of one or more logic components that receive one or more asynchronous clock domain crossings. The circuit design is traversed to determine whether a subset of the one or more asynchronous clock domain crossings does not pass through a signal having an attribute indicating that the signal is intended to be part of the one or more asynchronous clock domain crossings. If such a crossing exists, an error is indicated for the circuit design.
    Type: Application
    Filed: December 4, 2014
    Publication date: June 11, 2015
    Inventors: Gabor Drasny, Gavin B. Meil
  • Publication number: 20150161311
    Abstract: A design tool can implement phase algebra based design evaluation to evaluate a circuit design with a compact representation of numerous waveforms without simulating the individual waveforms. The design tool can determine two or more input sequences of signal transition representations associated with an input net of an indicated component in an RTL circuit design, where the two or more input sequences of signal transition representations are associated with a mode element. Each signal transition representation represents a nondeterministic transition from a previous signal state to possible signal state(s). The mode element indicates a selection between two or more output sequences of signal transition representations. It is determined, based on the indicated component and the mode element, two or more output sequences of signal transition representations derived from the input sequence(s) of signal transition representations.
    Type: Application
    Filed: November 19, 2014
    Publication date: June 11, 2015
    Inventors: Gabor Drasny, Gavin B. Meil
  • Publication number: 20150161315
    Abstract: Various implementations of a method, system and computer program product receive a circuit model that can include an asynchronous crossing between a first set of one or more logic components in a first clock domain and a second set of one or more logic components in a second clock domain. A shadow network can be constructed that corresponds to the asynchronous crossing, where the shadow network includes at least one of an asynchronous transition detector, an asynchronous sample detector, and a metastability timer. The shadow network can include shadow network signals corresponding to signals of the asynchronous crossing.
    Type: Application
    Filed: May 12, 2014
    Publication date: June 11, 2015
    Applicant: International Business Machines Corporation
    Inventor: Gavin B. Meil
  • Publication number: 20150161309
    Abstract: A design tool can implement phase algebra based design evaluation to evaluate a circuit design with a compact representation of numerous waveforms without simulating the individual waveforms. The design tool can determine an input sequence of signal transition representations associated with an input net of a component in a register transfer level circuit design, where each signal transition representation represents a nondeterministic transition from a previous signal state to one or more possible signal states. Determining the input sequence of signal transition representations includes determining that a subsequence of the input sequence of signal transition representations indicates at most one transition within the subsequence of the input sequence.
    Type: Application
    Filed: November 19, 2014
    Publication date: June 11, 2015
    Inventors: Gabor Drasny, Gavin B. Meil