Patents by Inventor Lakshmi N. Reddy

Lakshmi N. Reddy 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: 9672321
    Abstract: A system and method of performing physical synthesis of a chip design are described. The method includes performing a baseline physical synthesis to determine a timing slack associated with each device, the timing slack indicating a margin by which timing requirements for the associated device are exceeded, determining that a threshold has been exceeded, the determining based on an analysis of a histogram of the timing slack, and executing a stage-by-stage physical synthesis based on determining that the threshold has been exceeded. The executing the stage-by-stage physical synthesis includes running a stage of the stage-by-stage physical synthesis to determine real timing slack, mapping the real timing slack to virtual timing slack, and running a next stage of the stage-by-stage physical synthesis using the virtual timing slack.
    Type: Grant
    Filed: July 1, 2015
    Date of Patent: June 6, 2017
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Christopher J. Berry, Kaustav Guha, Lakshmi N. Reddy, Sourav Saha
  • Publication number: 20170004247
    Abstract: A system and method of performing physical synthesis of a chip design are described. The method includes performing a baseline physical synthesis to determine a timing slack associated with each device, the timing slack indicating a margin by which timing requirements for the associated device are exceeded, determining that a threshold has been exceeded, the determining based on an analysis of a histogram of the timing slack, and executing a stage-by-stage physical synthesis based on determining that the threshold has been exceeded. The executing the stage-by-stage physical synthesis includes running a stage of the stage-by-stage physical synthesis to determine real timing slack, mapping the real timing slack to virtual timing slack, and running a next stage of the stage-by-stage physical synthesis using the virtual timing slack.
    Type: Application
    Filed: August 27, 2015
    Publication date: January 5, 2017
    Inventors: Christopher J. Berry, Kaustav Guha, Lakshmi N. Reddy, Sourav Saha
  • Publication number: 20170004245
    Abstract: A system and method of performing physical synthesis of a chip design are described. The method includes performing a baseline physical synthesis to determine a timing slack associated with each device, the timing slack indicating a margin by which timing requirements for the associated device are exceeded, determining that a threshold has been exceeded, the determining based on an analysis of a histogram of the timing slack, and executing a stage-by-stage physical synthesis based on determining that the threshold has been exceeded. The executing the stage-by-stage physical synthesis includes running a stage of the stage-by-stage physical synthesis to determine real timing slack, mapping the real timing slack to virtual timing slack, and running a next stage of the stage-by-stage physical synthesis using the virtual timing slack.
    Type: Application
    Filed: July 1, 2015
    Publication date: January 5, 2017
    Inventors: Christopher J. Berry, Kaustav Guha, Lakshmi N. Reddy, Sourav Saha
  • Publication number: 20160275214
    Abstract: A method of performing physical aware technology mapping in a logic synthesis phase of design of an integrated circuit and a system to perform physical aware technology mapping are described. The method includes subdividing a core area representing a sub-block of the integrated circuit into equal-sized grids. The method also includes determining a location of each of one or more latches in the logic design based on an algorithm, determining a location of each of one or more combinational logic gates in the logic design based on the locations of the one or more latches, and obtaining the technology mapping based on the locations of the one or more latches, one or more input ports, or one or more output ports, the locations of the one or more combinational logic gates, and associated path delays.
    Type: Application
    Filed: May 27, 2016
    Publication date: September 22, 2016
    Inventors: Christopher J. Berry, Pinaki Chakrabarti, Lakshmi N. Reddy, Sourav Saha
  • Publication number: 20160275215
    Abstract: A method of performing physical aware technology mapping in a logic synthesis phase of design of an integrated circuit and a system to perform physical aware technology mapping are described. The system includes a memory device to store a logic design of the integrated circuit, and a processor to subdivide a core area representing a sub-block of the integrated circuit into equal-sized grids, the core area including one or more input ports and one or more output ports, to determine a location of each latch in a logic design based on an algorithm, to determine a location of each combinational logic gate in the logic design, and to obtain the technology mapping based on the locations of the one or more latches, the locations of the one or more combinational logic gates, and associated path delays.
    Type: Application
    Filed: June 1, 2016
    Publication date: September 22, 2016
    Inventors: Christopher J. Berry, Pinaki Chakrabarti, Lakshmi N. Reddy, Sourav Saha
  • Patent number: 9443047
    Abstract: A method of performing physical aware technology mapping in a logic synthesis phase of design of an integrated circuit and a system to perform physical aware technology mapping are described. The method includes subdividing a core area representing a sub-block of the integrated circuit into equal-sized grids. The method also includes determining a location of each of one or more latches in the logic design based on an algorithm, determining a location of each of one or more combinational logic gates in the logic design based on the locations of the one or more latches, and obtaining the technology mapping based on the locations of the one or more latches, one or more input ports, or one or more output ports, the locations of the one or more combinational logic gates, and associated path delays.
    Type: Grant
    Filed: May 28, 2014
    Date of Patent: September 13, 2016
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Pinaki Chakrabarti, Christopher J. Berry, Lakshmi N. Reddy, Sourav Saha
  • Patent number: 9443048
    Abstract: A method of performing physical aware technology mapping in a logic synthesis phase of design of an integrated circuit and a system to perform physical aware technology mapping are described. The system includes a memory device to store a logic design of the integrated circuit, and a processor to subdivide a core area representing a sub-block of the integrated circuit into equal-sized grids, the core area including one or more input ports and one or more output ports, to determine a location of each latch in a logic design based on an algorithm, to determine a location of each combinational logic gate in the logic design, and to obtain the technology mapping based on the locations of the one or more latches, the locations of the one or more combinational logic gates, and associated path delays.
    Type: Grant
    Filed: November 19, 2014
    Date of Patent: September 13, 2016
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Christopher J. Berry, Pinaki Chakrabarti, Lakshmi N. Reddy, Sourav Saha
  • Publication number: 20150347640
    Abstract: A method of performing physical aware technology mapping in a logic synthesis phase of design of an integrated circuit and a system to perform physical aware technology mapping are described. The method includes subdividing a core area representing a sub-block of the integrated circuit into equal-sized grids. The method also includes determining a location of each of one or more latches in the logic design based on an algorithm, determining a location of each of one or more combinational logic gates in the logic design based on the locations of the one or more latches, and obtaining the technology mapping based on the locations of the one or more latches, one or more input ports, or one or more output ports, the locations of the one or more combinational logic gates, and associated path delays.
    Type: Application
    Filed: May 28, 2014
    Publication date: December 3, 2015
    Applicant: International Business Machines Corporation
    Inventors: Christopher J. Berry, Pinaki Chakrabarti, Lakshmi N. Reddy, Sourav Saha
  • Publication number: 20150347643
    Abstract: A method of performing physical aware technology mapping in a logic synthesis phase of design of an integrated circuit and a system to perform physical aware technology mapping are described. The system includes a memory device to store a logic design of the integrated circuit, and a processor to subdivide a core area representing a sub-block of the integrated circuit into equal-sized grids, the core area including one or more input ports and one or more output ports, to determine a location of each latch in a logic design based on an algorithm, to determine a location of each combinational logic gate in the logic design, and to obtain the technology mapping based on the locations of the one or more latches, the locations of the one or more combinational logic gates, and associated path delays.
    Type: Application
    Filed: November 19, 2014
    Publication date: December 3, 2015
    Inventors: Christopher J. Berry, Pinaki Chakrabarti, Lakshmi N. Reddy, Sourav Saha
  • Patent number: 8966422
    Abstract: A computer implemented method for designing an integrated circuit includes: forming, on a computing device, a description of an initial layout of the integrated circuit, the layout including at least two paths, each of the two paths including an input, an output and an at least one combinational element; identifying critical paths in the initial layout; forming a median line between the input and the output for at least one of the critical paths; and moving a location of a combinational element in the at least one critical path from a first location to a second location to form a revised layout, the first location being further from the median line than the second location.
    Type: Grant
    Filed: January 7, 2014
    Date of Patent: February 24, 2015
    Assignee: International Business Machines Corporation
    Inventors: Lakshmi N. Reddy, Sourav Saha
  • Patent number: 8881089
    Abstract: A system, process, etc. according to some embodiments, which includes operations that include selecting one of a plurality of solutions (“selected solution”) for optimization of an integrated circuit design during physical synthesis. The operations can further include performing on the selected solution a fast evaluation of a specific metric without updating design documents (e.g., without updating a netlist or metric map). If the evaluation of the specific metric is non-satisfactory, then the candidate solution is rejected. If the evaluation of the specific metric is satisfactory, then a design document is updated and a full evaluation of the specific metric (and other metrics) can be performed.
    Type: Grant
    Filed: December 17, 2013
    Date of Patent: November 4, 2014
    Assignee: International Business Machines Corporation
    Inventors: Charles Jay Alpert, Glenn R. Bee, Zhuo Li, Tuhin Mahmud, Stephen T. Quay, Lakshmi N. Reddy, Chin Ngai Sze, Yaoguang Wei
  • Patent number: 8782584
    Abstract: A computer implemented method for reworking a plurality of cells initially placed in a circuit design. An expander allocates cells to tiles. The expander determines a high detailed routing cost tile class, wherein the high detailed routing cost tile class is a class of tiles that has high detailed routing costs. The expander selects a cell within a tile of the high detailed routing cost tile class to form a selected cell in a selected tile. The expander applies multiple techniques to reposition these cells at new locations to improve the detailed routability. The expander can place an expanded bounding box around the selected cell, wherein the bounding box extends to at least one tile adjacent the selected tile, and repositions the selected cell within the bounding box to form a modified design to improve the detailed routability. The expander may also inflate and legalize those cells.
    Type: Grant
    Filed: May 24, 2013
    Date of Patent: July 15, 2014
    Assignee: International Business Machines Corporation
    Inventors: Charles J Alpert, Zhuo D Li, Gi-Joon Nam, Shyam Ramji, Lakshmi N Reddy, Jarrod A Roy, Taraneh E Taghavi, Paul G Villarrubia, Natarajan Viswanathan
  • Patent number: 8677304
    Abstract: A task-based multi-process design synthesis methodology relies on a plurality of child processes to assist a parent process in performing optimizations on an integrated circuit design. Objects from an integrated circuit design are grouped into subsets and assigned to child processes, with each child process performing a transform on each of the objects in the subset assigned to that child process and determining which of the objects in the subset are candidate objects for which performance of the transform has been successful. The child processes then notify the parent process of those objects that qualify as candidate objects, so that the parent process only has to perform the transform on the candidate objects, thereby relieving the parent process from the overhead associated with performing the transform on non-candidate objects for which the transform has been determined by the child processes as not being successful.
    Type: Grant
    Filed: March 5, 2013
    Date of Patent: March 18, 2014
    Assignee: International Business Machines Corporation
    Inventors: Anthony D. Drumm, Jagannathan Narasimhan, Lakshmi N. Reddy, Louise H. Trevillyan, Brian C. Wilson
  • Publication number: 20130346938
    Abstract: A computer implemented method for reworking a plurality of cells initially placed in a circuit design. An expander allocates cells to tiles. The expander determines a high detailed routing cost tile class, wherein the high detailed routing cost tile class is a class of tiles that has high detailed routing costs. The expander selects a cell within a tile of the high detailed routing cost tile class to form a selected cell in a selected tile. The expander applies multiple techniques to reposition these cells at new locations to improve the detailed routability. The expander can place an expanded bounding box around the selected cell, wherein the bounding box extends to at least one tile adjacent the selected tile, and repositions the selected cell within the bounding box to form a modified design to improve the detailed routability. The expander may also inflate and legalize those cells.
    Type: Application
    Filed: May 24, 2013
    Publication date: December 26, 2013
    Applicant: International Business Machines Corporation
    Inventors: Charles J Alpert, Zhuo D Li, Gi-Joon Nam, Shyam Ramji, Lakshmi N Reddy, Jarrod A Roy, Taraneh E Taghavi, Paul G Villarrubia, Natarajan Viswanathan
  • Patent number: 8584070
    Abstract: Global routing congestion in an integrated circuit design is characterized by computing global edge congestions and constructing a histogram of averages of the global edge congestions for varying percentages of worst edge congestion, e.g., 0.5%, 1%, 2%, 5%, 10% and 20%. Horizontal and vertical global edges are handled separately. Global edges near blockages can be skipped to avoid false congestion hotspots. The histogram of the current global routing can be compared to a histogram for a previous global routing to select a best routing solution. The histograms can also be used in conjunction with congestion-driven physical synthesis tools.
    Type: Grant
    Filed: October 4, 2011
    Date of Patent: November 12, 2013
    Assignee: International Business Machines Corporation
    Inventors: Charles J. Alpert, Zhuo Li, Lakshmi N. Reddy, Chin Ngai Sze, Yaoguang Wei
  • Patent number: 8495534
    Abstract: A computer implemented method, data processing system, and computer program product for reworking a plurality of cells initially placed in a circuit design. An expander allocates cells to tiles. The expander determines a high detailed routing cost tile class, wherein the high detailed routing cost tile class is a class of tiles that has high detailed routing costs. The expander selects a cell within a tile of the high detailed routing cost tile class to form a selected cell in a selected tile. The expander applies multiple techniques to reposition these cells at new locations to improve the detailed routability. The expander can place an expanded bounding box around the selected cell, wherein the bounding box extends to at least one tile adjacent the selected tile, and repositions the selected cell within the bounding box to form a modified design to improve the detailed routability. The expander may also inflate and legalize those cells.
    Type: Grant
    Filed: June 8, 2010
    Date of Patent: July 23, 2013
    Assignee: International Business Machines Corporation
    Inventors: Charles J. Alpert, Zhuo D. Li, Gi-Joon Nam, Shyam Ramji, Lakshmi N. Reddy, Jarrod A. Roy, Taraneh E. Taghavi, Paul G. Villarrubia, Natarajan Viswanathan
  • Publication number: 20130086545
    Abstract: Global routing congestion in an integrated circuit design is characterized by computing global edge congestions and constructing a histogram of averages of the global edge congestions for varying percentages of worst edge congestion, e.g., 0.5%, 1%, 2%, 5%, 10% and 20%. Horizontal and vertical global edges are handled separately. Global edges near blockages can be skipped to avoid false congestion hotspots. The histogram of the current global routing can be compared to a histogram for a previous global routing to select a best routing solution. The histograms can also be used in conjunction with congestion-driven physical synthesis tools.
    Type: Application
    Filed: October 4, 2011
    Publication date: April 4, 2013
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Charles J. Alpert, Zhuo Li, Lakshmi N. Reddy, Chin Ngai Sze, Yaoguang Wei
  • Patent number: 8407652
    Abstract: A task-based multi-process design synthesis methodology relies on a plurality of child processes to assist a parent process in performing optimizations on an integrated circuit design. Objects from an integrated circuit design are grouped into subsets and assigned to child processes, with each child process performing a transform on each of the objects in the subset assigned to that child process and determining which of the objects in the subset are candidate objects for which performance of the transform has been successful. The child processes then notify the parent process of those objects that qualify as candidate objects, so that the parent process only has to perform the transform on the candidate objects, thereby relieving the parent process from the overhead associated with performing the transform on non-candidate objects for which the transform has been determined by the child processes as not being successful.
    Type: Grant
    Filed: December 20, 2010
    Date of Patent: March 26, 2013
    Assignee: International Business Machines Corporation
    Inventors: Anthony D. Drumm, Jagannathan Narasimhan, Lakshmi N. Reddy, Louise H. Trevillyan, Brian C. Wilson
  • Patent number: 8341565
    Abstract: A task-based multi-process design synthesis methodology is reproducible, and relies on a plurality of child processes to assist a parent process in performing optimizations on an integrated circuit design. Objects from an integrated circuit design are grouped into subsets and assigned to child processes, with each child process performing a transform on each of the objects in the subset assigned to that child process and determining which of the objects in the subset are candidate objects for which performance of the transform has been successful. Each child process also undoes the transform performed for each object such that the same initial state of the integrated circuit design is used to perform each transform. In addition, the parent process tracks the results of performing the transform by each child process, and applies successful transforms in a controlled sequence.
    Type: Grant
    Filed: December 20, 2010
    Date of Patent: December 25, 2012
    Assignee: International Business Machines Corporation
    Inventors: Anthony D. Drumm, Jagannathan Narasimhan, Lakshmi N. Reddy, Louise H. Trevillyan
  • Publication number: 20120159417
    Abstract: A task-based multi-process design synthesis methodology relies on a plurality of child processes to assist a parent process in performing optimizations on an integrated circuit design. Objects from an integrated circuit design are grouped into subsets and assigned to child processes, with each child process performing a transform on each of the objects in the subset assigned to that child process and determining which of the objects in the subset are candidate objects for which performance of the transform has been successful. The child processes then notify the parent process of those objects that qualify as candidate objects, so that the parent process only has to perform the transform on the candidate objects, thereby relieving the parent process from the overhead associated with performing the transform on non-candidate objects for which the transform has been determined by the child processes as not being successful.
    Type: Application
    Filed: December 20, 2010
    Publication date: June 21, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Anthony D. Drumm, Jagannathan Narasimhan, Lakshmi N. Reddy, Louise H. Trevillyan, Brian C. Wilson