International Business Machines Corporation

Smita Krishnaswamy

Ruchir Puri

Haoxing Ren

Victor N Kravets

Chin Ngai Sze

Minsik Cho

Joachim Keinert

Haifeng Qian

Matthew Mantell Ziegler

Hua Xiang

Louise Helen Trevillyan

Eli Arbel

Jagannathan Narasimhan

David L Rude

David John Geiger

Jeremy T Hopkins

John Mack Isakson

Dorothy Kucar

Nilesh A Modi

Two circuits, an original and a modified, are being recognized, with the original circuit having a first logic and the modified circuit having a second logic. The second logic contains at least one desired logic change relative to the first logic. An equivalence line is detected in the original circuit such that the first and second logic are equivalent from the circuit inputs to the equivalence line. At least one point of change is located amongst the logic gates that are neighboring the equivalence line. The points of change are accepted as verified if an observability condition is fulfilled. The observability condition is checked within a Boolean Satisfiability (SAT) formulation. Substitute logic for the verified points of change is derived using SAT and Boolean equation solving techniques, in such manner that the first logic becomes equivalent to the second logic.

Logic modification synthesis

Exemplary embodiments include a computer implemented method for large block and structured synthesis, the method including determining initial design data from starting points for a synthesis flow, receiving user-directed structuring is incorporated into the synthesis flow, applying logical synthesis on the initial design data, applying a physical design on the initial design data, determining whether circuit design parameters have been met and in response to circuit design parameters not being met, adjusting the circuit design parameters.

Converged large block and structured synthesis for high performance microprocessor designs

A computer executed method is disclosed which accepts an original circuit with an original logic, accepts a modified circuit, and synthesizes a difference circuit. The difference circuit represents changes that implement the modified circuit's logic for the original circuit. The synthesis may locate an output-side boundary in the original logic in such a manner that the original logic is free of logic changes in between the output-side boundary and the primary output elements of the original circuit. The disclosed synthesis may also locate an input-side boundary in the original logic in such a manner that the original logic is free of logic changes in between the input-side boundary and the primary input elements of the original circuit. A computer program products are also disclosed. The computer program product contains a computer useable medium having a computer readable program code embodied therein. The computer readable program code when executed on a computer causes the computer to carry out the methods of finding input and output side boundaries in an original logic, and synthesizing in between those boundaries a difference circuit representing logic changes.

Logic difference synthesis

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Smita Krishnaswamy