Abstract: A Computer-Aided Design (CAD) system operates according to a method (100) having the steps of placing (102) a plurality of cells of one or more circuits in a layout, generating (106) a plurality of fanin trees from the layout, applying (110) fanin tree embedding on the plurality of fanin trees, and generating (112) a new layout from the embedded fanin trees.

Abstract: A method, apparatus, and computer program product for performing density biased buffer insertion in an integrated circuit design are provided. A tiled Steiner tree topology map is used in which density values are associated with each tile in the map. A directed acyclic graph (DAG) is created over an initial set of potential candidate points. A subset of the candidate points is selected by associating costs with each tile, and with each path or edge, to each tile. The total costs associated with placement of a buffer at a position within each tile are calculated. The lowest cost tile is then selected as a candidate position for buffer insertion. This process is then repeated to obtain an asymmetrically distributed set of candidate buffer insertion points between a source and a sink.

Abstract: A mechanism for constructing Steiner trees using simultaneous blockage avoidance, delay optimization, and design density management are provided. An initial tiled timing-driven Steiner tree is obtained for an integrated circuit design. The Steiner tree is broken into 2-paths for which plates are generated designated the permissible area in which a Steiner point may migrate. Each 2-path is optimized by calculating a cost for each tile in the plate as a function of an environmental cost, a tile delay cost, and a trade-off value. A minimum cost tile is then selected as the point to which the Steiner point in the 2-path, if any, is to migrate. Once each 2-path is processed in this manner, routing is performed so as to minimize the cost at the source. This process may be iteratively repeated with new trade-off values until all of the nets have zero or positive slew.

Abstract: An apparatus and method for incorporating driver sizing into buffer insertion such that the two optimization techniques are performed simultaneously are provided. The apparatus and method extends van Ginneken's algorithm to handle driver sizing by treating a source node as a “driver library.” With the apparatus and method, the circuit design is converted to a Steiner tree representation of the circuit design. Buffer insertion is performed on the Steiner tree using the van Ginneken algorithm to generate a first set of possible optimal solutions. For each solution in the first set, a driver of the same type as the original driver in the Steiner tree is selected from a driver library and virtually inserted into the solution. A delay penalty is retrieved for the selected driver, which is then used long with the new driver's characteristics to generate a second set of solutions based o the first set of solutions.

Abstract: A method, apparatus, and computer program product for performing density biased buffer insertion in an integrated circuit design are provided. A tiled Steiner tree topology map is used in which density values are associated with each tile in the map. A directed acyclic graph (DAG) is created over an initial set of potential candidate points. A subset of the candidate points is selected by associating costs with each tile, and with each path or edge, to each tile. The total costs associated with placement of a buffer at a position within each tile are calculated. The lowest cost tile is then selected as a candidate position for buffer insertion. This process is then repeated to obtain an asymmetrically distributed set of candidate buffer insertion points between a source and a sink.

Abstract: A mechanism for constructing Steiner trees using simultaneous blockage avoidance, delay optimization, and design density management are provided. An initial tiled timing-driven Steiner tree is obtained for an integrated circuit design. The Steiner tree is broken into 2-paths for which plates are generated designated the permissible area in which a Steiner point may migrate. Each 2-path is optimized by calculating a cost for each tile in the plate as a function of an environmental cost, a tile delay cost, and a trade-off value. A minimum cost tile is then selected as the point to which the Steiner point in the 2-path, if any, is to migrate. Once each 2-path is processed in this manner, routing is performed so as to minimize the cost at the source. This process may be iteratively repeated with new trade-off values until all of the nets have zero or positive slew.

Abstract: An apparatus and method for incorporating driver sizing into buffer insertion such that the two optimization techniques are performed simultaneously are provided. In particular, the apparatus and method extends van Ginneken's algorithm to handle driver sizing by treating a source node as a “driver library”. With the apparatus and method, the circuit design is converted to a Steiner tree representation of the circuit design. Buffer insertion is performed on the Steiner tree using the van Ginneken algorithm to generate a first set of possible optimal solutions. For each solution in the first set, a driver of the same type as the original driver in the Steiner tree is selected from a driver library and virtually inserted into the solution. A delay penalty is retrieved for the selected driver. This delay penalty is then used along with the new driver's characteristics to generate a second set of solutions based on the first set of solutions.