Cadence Design Systems, Inc.

Altera Corporation

Athanasius Spyrou

Jun Li

Hsien-Yen Chiu

Hong Zhao

Arnold Ginetti

Harsh Vardhan

Electronic design automation tools may perform static timing analysis on an integrated circuit design. An integrated circuit design may have multiple nodes that can be traversed using a breadth-first search. To reduce the run-time of static timing analysis tools, tags recording arrival times associated with non-critical paths may have their consolidated in order to include only the critical timing information in the tag, thereby reducing the amount of data that is carried through to the analysis of the entire design. In a critical slack based merging method, a maximal arrival time associated with a circuit node may be compared to the remaining arrival times associated with the circuit node. Arrival times less than the maximal arrival time by an amount greater than a threshold amount may be deemed non-critical arrival times and may be removed from the tag for the circuit node.

Dynamic tag allocation for clock reconvergence pessimism removal

In one embodiment of the invention, a method is disclosed for modifying a pre-existing application program for multi-processing and/or distributed parallel processing. The method includes searching an application program for a computational loop; analyzing the computational loop to determine independence of the computational transactions of the computational loop; and replacing the computational loop with master code and slave code to provide master-slave execution of the computational loop in response to analyzing the computational loop to determine independence of the computational transactions of the computational loop. Multiple instances of the modified application program are executed to provide multi-processing and/or distributed parallel processing.

Software modification methods to provide master-slave execution for multi-processing and/or distributed parallel processing

In one embodiment of the invention, a method of analyzing a circuit design is disclosed. In the method of analyzing a circuit design, a circuit is levelized into multiple levels. Circuit simulations of elements at a level are determined using circuit simulators, one for each element and in parallel in level order. Topological circuit loops may be removed from the circuit. Circuit simulation of the circuit may be performed on the circuit using the circuit simulations determined by the circuit simulators at each level of the circuit.

Method and apparatus for circuit simulation using parallel computing

Disclosed is an improved approach for performing crosstalk and signal integrity analysis in which multiple variables are taken into account when analyzing the effects of on-chip crosstalk, such as for example coupled wire length, ratio of coupling capacitance, and aggressor and victim driver types. Rather than performing a full-chip simulation, the potential crosstalk effects can be pre-characterized by performing simulation/modeling over specific net portions by systematically changing the values of these multiple variables. A set of patterns characterized from the variables are formed from the modeling. During the analysis process, the IC design is checked of the presence of the patterns, from which is produced the expected delay impact for crosstalk in the design.

Method and system for performing crosstalk analysis

Disclosed is an improved approach for performing crosstalk and signal integrity analysis in which multiple variables are taken into account when analyzing the effects of on-chip crosstalk, such as for example coupled wire length, ration of coupling capacitance, and aggressor and victim driver types. Rather than performing a full-chip simulation, the potential crosstalk effects can be pre-characterized by performing simulation/modeling over specific net portions by systematically changing the values of these multiple variables. A set of patterns characterized from the variables are formed from the modeling. During the analysis process, the IC design is checked of the presence of the patterns, from which is produced the expected delay impact for crosstalk in the design.

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Sunnyvale, CA, United States of America

Athanasius Spyrou