Digital netlist partitioning system for faster circuit reverse-engineering
AssigneeChipworks
InventorMichael Green
Life of this patent
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Abstract
Methods and systems are provided to reduce the complexity of sequential digital circuitry including cells of unknown function by grouping and defining like instance of combinational circuitry cells. The system groups together cells that feed into the same combination of one or more state cells. The groups of cells are then replaced by clouds which are defined in the netlist for the sequential digital circuitry to produce a simpler representation of the circuitry for analysis purposes and to aid in determining the function of those cells for which the function is unknown.
Claims18
A method of reducing complexity of a digital circuit comprising:
- providing circuitry for analysis comprising a plurality of cells, wherein at least some of the plurality of cells have an unknown function;
- categorizing each of the plurality of cells as either a combinational cell or a state cell, wherein the plurality of cells comprise a plurality of combinational cells and a plurality of state cells;
- identifying by a computer a first combinational cell group among the plurality of combinational cells that each affect a same portion of the plurality of state cells;
- and
- replacing the first combinational cell group with a first cloud.
A computer program product comprising computer instructions stored on a nontransitory computer readable medium for reducing complexity of a digital circuit, said computer instructions upon being executed on a computer are configured to perform activities comprising:
- providing circuitry for analysis comprising a plurality of cells, wherein at least some of the plurality of cells have an unknown function;
- categorizing each of the plurality of cells as either a combinational cell or a state cell, wherein the plurality of cells comprise a plurality of combinational cells and a plurality of state cells;
- identifying a first combinational cell group among the plurality of combinational cells that each affect a same portion of the plurality of state cells;
- and
- replacing the first combinational cell group with a first cloud.
Dependencies are inferred from the claim text.