摘要:
Some embodiments of the present invention provide techniques and systems for determining whether a high-level model (HLM) for a circuit design is equivalent to a register-transfer-level (RTL) model for the circuit design. During operation, a system can identify a set of checkpoints. Each checkpoint can be associated with a characteristic function defined over the states of a finite-state-machine (FSM) representation of the HLM, a characteristic function defined over the states of an FSM representation of the RTL model, and an invariant defined over a set of variables in the HLM and a set of registers in the RTL model. Next, the system can generate a set of invariant proof problems, wherein each invariant proof problem corresponds to a transition between two checkpoints in the set of checkpoints. The system can then determine whether the HLM is equivalent to the RTL model by solving the set of invariant proof problems.
摘要:
A system and method are provided for conducting a client-server application (e.g., instant messaging, VoIP telephony) using non-persistent communications. Clients issue periodic heartbeat messages to a connectionless server using a non-persistent (e.g., UDP) communication protocol. The heartbeat messages identify the clients by unique client identifiers. When an application server has an unsolicited communication for a client (e.g., a new instant message, a VoIP call), the application server retrieves the client's address from the connectionless server if it does not already have the address. The application server forwards the unsolicited communication to the client via a non-persistent communication, and may spoof the connectionless server if necessary to reach the client through a firewall, proxy, NAT or similar entity. Clients that cannot use non-persistent protocols establish persistent connections with a client manager. The client manager issues heartbeat messages to the connectionless server and receives and forwards unsolicited communications for these clients.
摘要:
A controller operable to control an array of processing elements comprises a retrieval unit operable to retrieve instruction items for each of a plurality of instructions streams, each instruction stream having a plurality of instructions items, a combining unit operable to combine the plurality of instruction streams into a serial instruction stream, and a distribution unit operable to distribute the serial instruction stream to an array of processing elements.
摘要:
In order to provide filtering of clock noise from an integrated circuit at least one differential signal line connected to the integrated circuit is provided with an embedded common mode filter. The common mode filter can be provided in the form of a hollowed out portion of an impedance reference plane.
摘要:
One embodiment of the present invention provides a system that secures a database configuration from undesired modifications. This system allows a security officer to issue a configuration-locking command, which activates a lock for the configuration of a database object. When a configuration lock is activated for a database object, the system prevents a user (e.g., a database administrator) from modifying the configuration of the database object, without restricting the user from accessing the database object itself. The security officer is a trusted user that is responsible for maintaining the stability of the database configuration, such that a configuration lock activated by the security officer preserves the database configuration by overriding the privileges assigned to a database administrator.
摘要:
Methods and apparatuses are described for sharing inductive invariants while performing formal verification of a circuit design. Specifically, some embodiments assume at least an inductive invariant for a property to be true while proving another property. According to one definition, an inductive invariant of a property is an inductive assertion such that all states that satisfy the inductive assertion also satisfy the property. According to one definition, an inductive assertion describes a set of states that includes all legal initial states of the circuit design and that is closed under a transition relation that models the circuit design.
摘要:
A processing technique facilitating the fabrication of the integrated circuit with microsprings at different vertical positions relative to a surface of a substrate is described. During the fabrication technique, microsprings are lithographically defined on surfaces of a first substrate and a second substrate. Then, a hole is created through a first substrate. Moreover, the integrated circuit may be created by rigidly mechanically coupling the two substrates to each other such that the microsprings on the surface of the second substrate are within a region defined at least in part by an edge around the hole. Subsequently, photoresist that constrains the microsprings on the surfaces of the two substrates may be removed. In this way, microsprings at the different vertical positions can be fabricated.
摘要:
One embodiment of the present invention provides an integrated circuit chip, including an active face upon which active circuitry and signal pads reside, and a back face opposite the active face. The integrated circuit chip additionally comprises an electromagnetic via that facilitates communication between signal pads on the integrated circuit chip and signal pads on a second integrated circuit chip. The electromagnetic via couples a signal pad on the active face of the integrated circuit chip to the back face of the integrated circuit chip so that the integrated circuit chip can communicate with the second integrated circuit chip while the back face of the integrated circuit chip is adjacent to the active face of the second integrated circuit chip. Moreover, the electromagnetic via operates by facilitating non-conductive signaling through the integrated circuit chip.
摘要:
One embodiment provides a method for determining mask layouts. During operation, the system can receive a design intent. Next, the system can determine a set of critical edges in the design layout, and select a first edge and a second edge. The system can then determine a first trench and a second trench using the first edge and the second edge, respectively. Note that an edge of the first trench may substantially overlap with the first edge, and an edge of the second trench may substantially overlap with the second edge. Next, the system may assign the first trench and the second trench to the first mask layout and the second mask layout, respectively. The system can then increase the first trench and the second trench, thereby improving pattern fidelity. The resulting mask layouts may be used in a double patterning process.
摘要:
A system and method for emulating the input/output performance of an application. A workload description language is used to produce a small but accurate model of the application, which is flexible enough to emulate the application's performance with varying underlying system configurations or operating parameters. The model describes I/O operations performed by the application, and reflects any dependencies that exist between different application threads or processes. The model is then executed or interpreted with a particular system configuration, and various parameters of the I/O operations may be set at the model's run-time. During execution, the input/output operations described in the model are generated according to the specified parameters, and are performed. The system configuration and/or I/O operation parameters may be altered and the model may be re-run.