Altera Corporation

Boris Ratchev

Gregg William Baeckler

Mike Hutton

David Wolk Mendel

Vaughn Betz

James G Schleicher

Stephen D Brown

Babette Van Antwerpen

Terry Borer

Richard Yuan

Kevin Chan

Ian Chesal

Yaska Sankar

Bruce B Pedersen

Yean-Yow Hwang

Techniques for optimizing the placement and synthesis of a circuit design on a programmable integrated circuit are provided. The performance of a circuit design is analyzed after it has been compiled with different values for selected input parameters. The input parameter values that produce the best results for an output metric are then chosen to synthesis and place the circuit design on the programmable integrated circuit. In one embodiment, the values of the output metrics are averaged for all test compiles that share the same input parameters, but different seeds. In another embodiment, the compile with the best output metrics, as determined by the user, are selected. These techniques allow a user to automatically trade off compile-time to get a better-optimized circuit.

Techniques for automated sweeping of parameters in computer-aided design to achieve optimum performance and resource usage

A technique of minimizes circuit area on programmable logic with fracturable logic elements by using 'balancing' in the technology mapping stage of the programmable logic computer-aided-design flow. A fracturable LE can be used for logic implementation in many ways, such as being used as one maximum-sized look-up table (LUT) or multiple smaller LUTs. One of more inputs of the multiple smaller LUTs may be shared. By balancing, this means mean that the technology mapping algorithm is tuned to use more small LUTs and fewer maximum-sized LUTs to implement the circuit. Although this is counterintuitive since the larger LUTs are more effective at absorbing gates, the technique achieves a smaller final circuit area by packing small LUTs into fracturable LEs.

Technology mapping technique for fracturable logic elements

Methods and code for verifying that modifications or improvements to a synthesizer algorithm do not introduce errors. Specifically, a number or VHDL or Verilog models are chosen. Two netlists are then synthesized from each modeled circuit, once using a unmodified or trusted synthesizer, and once using the modified or improved synthesizer. For each circuit, a set of input test vectors are generated. These vectors are somewhat random in nature, but modified or generated intelligently using knowledge about the circuit to be testing. For each circuit, each netlist is simulated, generating a set of output vectors. These output vectors are compared. If the output vectors match each other for each of the circuits tested, there is a high probability that the improved or modified synthesizer is not introducing new errors into the netlist.

Verifying logic synthesizers

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Sunnyvale, CA, United States of America

Boris Ratchev