Cadence Design Systems, Inc.

O-in Design Automation, Inc.

Other

Mentor Graphics Corporation

Jean-Charles Giomi

Chian-Min Richard Ho

Ping Fai Yeung

Kalyana C Mulam

Tai An Ly

Lawrence Curtis Widdoes, Jr

Jing Chyuarn Lin

Paul Andrew Wilcox

Robert Kristianto Mardjuki

David Lansing Dill

Paul Ii Estrada

Sabyasachi Das

Paul Estrada, Ii

Paul Il Estrada

Tsuwei Ku

Samir Agrawal

In one embodiment of the invention, an integrated circuit (IC) design tool is provided for synthesizing logic, including one or more software modules to synthesize a gate-level netlist of a squarer functional block. The software modules include a bitvector generator, a bitvector reducer, and a hybrid multibit adder generator. The bitvector generator multiplies bits of a vector together to generate partial products for a plurality of bitvectors and then optimizes a plurality of least significant bitvectors. The bitvector reducer reduces the partial products in the bitvectors of the squarer functional block down to a pair of final vectors. The hybrid multibit adder generator generates a hybrid multibit adder including a first adder and a second adder coupled together by a carry bit with bit widths being responsive to a dividerbit. The hybrid multibit adder adds the pair of final vectors together to generate a final result for the squarer functional block.

Synthesis of fast squarer functional blocks

In one embodiment of the invention, a method of logic synthesis is disclosed. The method includes generating a plurality of design architecture alternatives for circuit logic of a data path cluster; saving the plurality of design architecture alternatives; and evaluating the plurality of design architecture alternatives in response to design constraints to select a preferred design architecture.

Methods and apparatus for data path cluster optimization

In one embodiment of the invention, an integrated circuit (IC) design tool is provided that has a sum-of-products (SOP) synthesizer. The SOP synthesizer receives expected arrival times of signals including partial product terms of each bit-vector of a SOP functional block, a comparison gate delay, and a register-transfer-level (RTL) netlist in order to synthesize a gate-level netlist of the SOP functional block. The SOP synthesizer includes software modules to synthesize a partial products generator, a partial product reduction tree, and an adder. The synthesis of the partial product reduction tree is responsive to a comparison gate delay and the expected arrival times of the partial product terms in each bit vector.

Timing driven synthesis of sum-of-product functional blocks

A programmed computer searches for functional defects in a description of a circuit undergoing functional verification in the following manner. The programmed computer simulates the functional behavior of the circuit in response to a test vector, automatically restores the state of the simulation without causing the simulation to pass through a reset state, and then simulates the functional behavior of the circuit in response to another test vector. A predetermined rule can be used to identify test vectors to be simulated, and the predetermined rule can depend upon a measure of functional verification, including the number of times during simulation when a first state transition is performed by a first-controller at the same time as a second state transition is performed by a second controller. During simulation of the test vectors, manually generated tests or automatically generated checkers can monitor portions of the circuit for defective behavior.

Method for automatically searching for functional defects in a description of a circuit

A programmed computer generates descriptions of circuits (called 'checkers') that flag functional defects in a description of a circuit undergoing functional verification. The programmed computer automatically converts the circuit's description into a graph, automatically examines the graph for instances of a predetermined arrangement of nodes and connections, and automatically generates instructions that flag a behavior of a device represented by the instance in conformance with a known defective behavior. The checkers can be used during simulation or emulation of the circuit, or during operation of the circuit in a semiconductor die. The circuit's description can be in Verilog or VHDL and the automatically generated checkers can also be described in Verilog or VHDL. Therefore, the checkers can co-simulate with the circuit, monitoring the simulated operation of the circuit and flagging defective behavior. The programmed computer can automatically determine load conditions of registers in the circuit and automatically generate checkers to flag data loss in the registers. Some of the checkers may use signals generated by other checkers.

Method for automatically generating checkers for finding functional defects in a description of circuit

A programmed computer searches for functional defects in a description of a circuit undergoing functional verification in the following manner. The programmed computer simulates the functional behavior of the circuit in response to a test vector, automatically restores the state of the simulation without causing the simulation to pass through a reset state, and then simulates the functional behavior of the circuit in response to another test vector. A predetermined rule can be used to identify test vectors to be simulated, and the predetermined rule can depend upon a measure of functional verification, including the number of times during simulation when a first state transition is performed by a first controller at the same time as a second state transition is performed by a second controller. During simulation of the test vectors, manually generated tests or automatically generated checkers can monitor portions of the circuit for defective behavior.

A programmed computer generates descriptions of circuits (called &ldquo;checkers&rdquo;) that flag functional defects in a description of a circuit undergoing functional verification. The programmed computer automatically converts the circuit's description into a graph, automatically examines the graph for instances of a predetermined arrangement of nodes and connections, and automatically generates instructions that flag a behavior of a device represented by the instance in conformance with a known defective behavior. The checkers can be used during simulation or emulation of the circuit, or during operation of the circuit in a semiconductor die The circuit's description can be in Verilog or VHDL and the automatically generated checkers can also be described in Verilog or VHDL. Therefore, the checkers can co-simulate with the circuit, monitoring the simulated operation of the circuit and flagging detective behavior. The programmed computer can automatically determine load conditions of registers in the circuit and automatically generate checkers to flag data loss in the registers. Some of the checkers may use signals generated by other checkers.

Method for automatically generating checkers for finding functional defects in a description of a circuit

A programmed computer generates descriptions of circuits (called &ldquo;checkers&rdquo;) that flag functional defects in a description of a circuit undergoing functional verification. The programmed computer automatically converts the circuit's description into a graph, automatically examines the graph for instances of a predetermined arrangement of nodes and connections, and automatically generates instructions that flag a behavior of a device represented by the instance in conformance with a known defective behavior. The checkers can be used during simulation or emulation of the circuit, or during operation of the circuit in a semiconductor die. The circuit's description can be in Verilog or VHDL and the automatically generated checkers can also be described in Verilog or VHDL. Therefore, the checkers can co-simulate with the circuit, monitoring the simulated operation of the circuit and flagging defective behavior. The programmed computer can automatically determine load conditions of registers in the circuit and automatically generate checkers to flag data loss in the registers. Some of the checkers may use signals generated by other checkers.

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Menlo Park, CA, United States of America

Jean-Charles Giomi