Abstract: A method, apparatus, and computer readable medium for synchronizing a main thread and a slave thread executing on a processor system are disclosed. For example, the method includes the following elements: transitioning the slave thread from a sleep state to a spin-lock state in response to a wake-up message from the main thread; transitioning the slave thread out of the spin-lock state to process a first work unit from the main thread; determining, at the main thread, an elapsed time period until receipt of a second work unit for the slave thread; transitioning the slave thread to the spin-lock state if the elapsed time period satisfies a threshold time period; and transitioning the slave thread to the sleep state if the elapsed time period does not satisfy the threshold time period.

Abstract: Within a system comprising a plurality of processors and a memory, a method of determining routing information for a circuit design for implementation within a programmable integrated circuit can include determining that nets of the circuit design comprise overlap and unrouting nets comprising overlap. A congestion picture can be determined that comprises costs of routing resources for the integrated circuit wherein the cost of a routing resource comprises a measure of historical congestion and a measure of current congestion, and wherein unrouted nets do not contribute to the measures of current congestion in the congestion picture. The method further can include concurrently routing a plurality of the unrouted nets via the plurality of processors executing in parallel according to the congestion picture and storing routing information for nets of the circuit design in the memory.

Abstract: A method is described that includes: determining that nets of the circuit design comprise overlap, where the overlap indicates that at least two of the nets of the circuit design use a same routing resource; dividing the nets with overlap among a plurality of buckets, where for each bucket, a net of the bucket does not overlap any other net in the bucket; sequentially processing each bucket by unrouting and rerouting, via at least one processor, nets in the bucket; and storing routing information specifying routes for nets of the circuit design.

Abstract: A method of placing a circuit design in logic blocks of an integrated circuit is disclosed. The method comprises receiving a circuit design to be implemented in the logic blocks of the integrated circuit; determining clock skew for a clock tree providing clock signals to a plurality of memory elements of the integrated circuit; evaluating timing requirements associated with the circuit design; and transforming the circuit design to a placement configuration, wherein the placement configuration places the circuit design in the logic blocks of the integrated circuit according to the timing requirements of the circuit design and the clock skew for the clock tree.

Abstract: A method is provided whereby a placement-based cost function is utilized to minimize leakage and dynamic power that is consumed by clock networks implemented within integrated circuits (ICs) such as field programmable gate arrays (FPGAs). An initial placement of clock signal loads is analyzed to determine whether an alternative placement of clock signal loads results in the reduction of the usage of vertical clock spines, or equivalently, the optimization of the cost function. Several desirable characteristics are obtained through strategic clock signal load placement within the FPGA in accordance with the cost function. First, the number of clock regions spanned by a particular clock signal is minimized. Second, interconnect capacitance within the clock region is also minimized. By minimizing the total capacitance of a particular clock network implemented within a clock region, the leakage and dynamic power consumed by the clock network within the clock region is also minimized.

Abstract: Nets of a logic design are efficiently routed in a programmable logic device, which includes multiple types of programmable interconnects. Patterns are read from a library in a storage device. Each pattern includes an ordered set of the types of the programmable interconnects. A path is determined from the source to the destination for each net of the logic design. The path is through a sequence of the programmable interconnects having types that correspond to each type in the ordered set of a selected pattern. A description is output of the path for each of the nets.

Abstract: Disclosed are processor-implemented methods for technology mapping a logic network onto programmable logic resources of a programmable logic device. The methods include determining respective Boolean flexibility values for a plurality of functionally equivalent mappings of the logic network onto the programmable logic resources, selecting one of the mappings as a function of the respective Boolean flexibility values, and storing the selected mapping.

Abstract: Method and apparatus for facilitating signal routing within a programmable logic device having routing resources is described. In an example, the routing resources are formed into groups where, for each of the groups, the routing resources are of a same type. Pairs of the groups are related by an association of at least one routing resource in one group of a pair of groups capable of being electrically connected to at least one other routing resource in another group of the pair of groups.

Abstract: A method of reducing power of a circuit is described. The method includes determining at least one unused selection input associated with stages of a multiplexer tree; pulling the at least one unused selection input to a constant value; and assigning predetermined values to unused data inputs of the multiplexer tree associated with the at least one unused selection input.

Abstract: A filter system for use in an automobile engine includes a filter unit fluidically interposed between a fluid pump of the engine and a heater core of the engine. The filter unit includes an inner core removably mounted in an outer case. The inner core includes a fluid permeable wall which filters fluid as the fluid passes through the filter unit.

Abstract: Various approaches for generating an implementation of an electronic circuit design are disclosed. In one approach, one or more configuration bits that have don't care conditions are identified for a LUT block of a design. A dynamic power state for a subset of a first level of logic devices in the LUT block is determined as a function of each identified configuration bit that has a don't care condition. A dynamic power state for a subset of a second level of logic devices is determined as a function of the determined power state for the first level of logic devices. A respective value for each identified configuration bit of the LUT is selected in response to the determined dynamic power states. The respective value is placed into the design for each identified configuration bit.

Abstract: A computer-implemented method of performing a Computer-Aided Design (CAD) flow on a circuit design for a programmable logic device (PLD) can include inserting a preprocessing task into the CAD flow prior to a selected task that does not recognize a constraint, wherein the preprocessing task introduces a modification into the circuit design according to the constraint. The circuit design including the modification can be processed through the selected task of the CAD flow. A reversal task can also be inserted into the CAD flow, wherein the reversal task removes the modification introduced into the circuit design by the preprocessing task. The method further can include processing the circuit design through at least one other task of the CAD flow and outputting the processed circuit design.

Abstract: A filter system for use in an automobile engine includes a filter unit fluidically interposed between a fluid pump of the engine and a heater core of the engine. The filter unit includes an inner core removably mounted in an outer case. The inner core includes a fluid permeable wall which filters fluid as the fluid passes through the filter unit.

Abstract: Method and apparatus are described for a placer system for placing design objects onto an arrayed architecture, such as a programmable logic device including an FPGA. More particularly, a placer interface is described for communicating with a placer core. The placer interface receives information from external entities, and unifies and generalizes this information for the placer core. The external entities comprise different representations of architecture, design, device, constraints and algorithm-dictated placer-movable objects.

Abstract: A filter system for use in an automobile engine includes a filter unit fluidically interposed between a fluid pump of the engine and a heater core of the engine. The filter unit includes an inner core removably mounted in an outer case. The inner core includes a fluid permeable wall which filters fluid as the fluid passes through the filter unit.

Abstract: Method and apparatus for facilitating signal routing within a programmable logic device having routing resources is described. In an example, the routing resources are formed into groups where, for each of the groups, the routing resources are of a same type. Pairs of the groups are related by an association of at least one routing resource in one group of a pair of groups capable of being electrically connected to at least one other routing resource in another group of the pair of groups.

Abstract: Application of network flow techniques to constrained optimization problems is disclosed. The present of constrains may lead to infeasible solutions. The infeasible solutions can be removed by an iterative process of changing the structure of the network and/or the associated parameters. Specific applications of the invention to the placement of tristate buffers and clocks in integrated circuits are disclosed.

Abstract: A method for completing the routing of a partially routed design is provided. The unrouted pins are routed to generate a first plurality of nets that may contain shorts or overlaps between the nets. The nets are analyzed to obtain timing information, and then divided into a set of critical and a set of non-critical nets. The non-critical nets are hidden, and the critical nets are rerouted to remove overlaps. The non-critical nets are then unhidden. The non-critical nets and rerouted critical nets are then rerouted so as to remove overlaps.

Abstract: A method for post-layout timing optimization is disclosed. The method performs timing analysis on a design to obtain timing information such as critical paths and slack values. Incremental placement based on the timing information is performed. A new routed design is generated by applying incremental routing to the result of incremental placement. The routed design is stored if its performance is better than the previous routed design. The above steps are repeated until a predetermined criterion is met.

Abstract: A systematic method for calculating future cost is disclosed. Pre-routing is performed from a source node to other nodes through a series of neighboring nodes. At each node in the pre-routing, the cumulative routing cost and Manhattan distance are calculated. This cumulative routing cost is used as a new future cost for a specific distance if it is lower than or there is no existing future cost for that distance. A table can be used to store the future cost data. During routing, the recorded future cost is added to the cumulative cost of a node to help guide the routing, improving router run-time.