Synopsys, Inc.

Peiqing Zou

Russell B Segal

Balkrishna R Rashingkar

Douglas Chang

David L Peart

Yan Lin

Neeraj Kaul

Leonardos J Van Bokhoven

Aiguo Lu

Leonardus J Van Bokhoven

Systems and methods are described for creating a netlist abstraction that provides full-chip context for performing circuit design floorplanning. The netlist abstraction can include a top-level netlist abstraction that corresponds to the top-level portion of the netlist, and a physical block netlist abstraction for each physical block in the circuit design. Each physical block netlist abstraction can retain macros that are in the physical block.

Netlist abstraction for circuit design floorplanning

Embodiments are described in which shaping is integrated with power network synthesis (PNS) for power grid (PG) alignment. Specifically, some embodiments create placement constraints based on the PG that is expected to be created by PNS, and then perform shaping (or perform legalization) on the circuit design based on the placement constraints. This ensures that the physical partitions (e.g., instances of multiply-instantiated-blocks) are aligned with the power grid during shaping.

Shaping integrated with power network synthesis (PNS) for power grid (PG) alignment

Systems and techniques for determining a set of timing paths for creating a circuit abstraction are described. During operation, an embodiment can receive a set of circuit elements in the circuit design that are candidates for optimization. Next, the embodiment can determine a set of timing paths by identifying critical timing paths in the circuit design whose delay is affected by a change in an input capacitance of a circuit element in the set of circuit elements. The embodiment can then identify a set of side loads based on the set of timing paths, and can create the circuit abstraction by retaining circuit elements and nets on each timing path in the set of timing paths, and retaining an identifier for each side load in the set of side loads. The circuit abstraction can then be used to update timing information during optimization of the circuit element.

Determining a set of timing paths for creating a circuit abstraction

Systems and techniques for creating a circuit abstraction are described. During operation, an embodiment can identify a set of side loads based on a set of timing paths. According to one definition, a side load of a timing path is a circuit element that is not on the timing path (i.e., the timing path does not pass through the circuit element), but whose input is electrically connected to an output of at least one circuit element that is on the timing path. Next, the embodiment can creating the circuit abstraction by retaining circuit elements and nets on each timing path in the set of timing paths, and retaining an identifier for each side load in the set of side loads. The circuit abstraction can then be used to update timing information during one or more stages of an electronic design automation flow.

Abstract creation

One embodiment of the present invention provides a system that scales an I/O-cell placement during die-size optimization. During operation, the system starts by receiving an initial die-size for a die and an initial I/O-cell placement for a set of I/O cells. The system also receives a target die-size for the die. The system then determines die-size changes between the initial die-size and the target die-size. Next, the system identifies available spaces between the set of I/O cells in the initial I/O-cell placement. The system subsequently scales the initial I/O-cell placement based on the identified available spaces and the die-size changes to obtain a new I/O-cell placement which fits in the target die-size.

Growing community of inventors

San Jose, CA, United States of America

Peiqing Zou