Abstract: A method and apparatus within a processing system is provided for associating shadow register sets with interrupt routines. The invention includes a vector generator that receives interrupts, and generates exception vectors to call interrupt routines that correspond to the interrupts. The exception vector considers the type of interrupt and the priority level of the interrupt when selecting the exception vector. Shadow set mapping logic is coupled to the vector generator. The mapping logic contains a number of fields that correspond to the different exception vectors that may be generated. The fields are programmable by kernel mode instructions, and contain data mapping each field to one of a number of shadow register sets. When an interrupt occurs, the vector generator generates a corresponding exception vector. In addition, the shadow set mapping logic looks at the field corresponding to the exception vector, and retrieves the data stored therein.

Abstract: A method and apparatus within a processing system is provided for associating shadow register sets with interrupt routines. The invention includes a vector generator that receives interrupts, and generates exception vectors to call interrupt routines that correspond to the interrupts. The exception vector considers the type of interrupt and the priority level of the interrupt when selecting the exception vector. Shadow set mapping logic is coupled to the vector generator. The mapping logic contains a number of fields that correspond to the different exception vectors that may be generated. The fields are programmable by kernel mode instructions, and contain data mapping each field to one of a number of shadow register sets. When an interrupt occurs, the vector generator generates a corresponding exception vector. In addition, the shadow set mapping logic looks at the field corresponding to the exception vector, and retrieves the data stored therein.

Abstract: A processor having a compare extension of an instruction set architecture which incorporates a set of high performance floating point operations. The instruction set architecture incorporates a variety of data formats including single precision and double precision data formats, as well as the paired-single data format that allows two simultaneous operations on a pair of operands. The extension includes instructions directed to a magnitude compare of floating point numbers and conversions between a pair of 32-bit fixed point integers and paired-single floating point format.

Abstract: A method and apparatus within a processing system is provided for associating shadow register sets with interrupt routines. The invention includes a vector generator that receives interrupts, and generates exception vectors to call interrupt routines that correspond to the interrupts. The exception vector considers the type of interrupt and the priority level of the interrupt when selecting the exception vector. Shadow set mapping logic is coupled to the vector generator. The mapping logic contains a number of fields that correspond to the different exception vectors that may be generated. The fields are programmable by kernel mode instructions, and contain data mapping each field to one of a number of shadow register sets. When an interrupt occurs, the vector generator generates a corresponding exception vector. In addition, the shadow set mapping logic looks at the field corresponding to the exception vector, and retrieves the data stored therein.

Abstract: A method and apparatus within a processing system is provided for associating shadow register sets with interrupt routines. The invention includes a vector generator that receives interrupts, and generates exception vectors to call interrupt routines that correspond to the interrupts. The exception vector considers the type of interrupt and the priority level of the interrupt when selecting the exception vector. Shadow set mapping logic is coupled to the vector generator. The mapping logic contains a number of fields that correspond to the different exception vectors that may be generated. The fields are programmable by kernel mode instructions, and contain data mapping each field to one of a number of shadow register sets. When an interrupt occurs, the vector generator generates a corresponding exception vector. In addition, the shadow set mapping logic looks at the field corresponding to the exception vector, and retrieves the data stored therein.

Abstract: An apparatus for reducing instruction re-fetching in a multithreading processor configured to concurrently execute a plurality of threads is disclosed. The apparatus includes a buffer for each thread that stores fetched instructions of the thread, having an indicator for indicating which of the fetched instructions in the buffer have already been dispatched for execution. An input for each thread indicates that one or more of the already-dispatched instructions in the buffer has been flushed from execution. Control logic for each thread updates the indicator to indicate the flushed instructions are no longer already-dispatched, in response to the input. This enables the processor to re-dispatch the flushed instructions from the buffer to avoid re-fetching the flushed instructions. In one embodiment, there are fewer buffers than threads, and they are dynamically allocatable by the threads. In one embodiment, a single integrated buffer is shared by all the threads.

Abstract: A method and apparatus for overlaying hazard clearing with a jump instruction within a pipeline microprocessor is described. The apparatus includes hazard logic to detect when a jump instruction specifies that hazards are to be cleared as part of a jump operation. If hazards are to be cleared, the hazard logic disables branch prediction for the jump instruction, thereby causing the jump instruction to proceed down the pipeline until it is finally resolved, and flushing the pipeline behind the jump instruction. Disabling of branch prediction for the jump instruction effectively clears all execution and/or instruction hazards that preceded the jump instruction. Alternatively, hazard logic causes issue control logic to stall the jump instruction for n-cycles until all hazards are cleared. State tracking logic may be provided to determine whether any instructions are executing in the pipeline that create hazards. If so, hazard logic performs normally.

Abstract: A method and apparatus for preventing duplicate matching entries in a TLB is disclosed. Each entry in the TLB has an Include bit that specifies whether to include or exclude the entry in tag match determinations. When a TLB write is attempted, if the write tag matches a tag in an entry of the TLB, the entry's Include bit is cleared so that the entry is excluded in subsequent match determinations. Furthermore, if the matching entry is an entry other then the entry to be written, and the matching entry is valid, and the value to be written to the entry is valid, then an exception is generated and the write is aborted. When an entry is successfully written, its Include bit is set so that the entry is included in subsequent match determinations. The Include bit is also used to qualify tag lookup match determinations.

Abstract: An intraocular lens for use as an artificial lens impant in the posterior chamber of the human eye adjacent the posterior capsule, after extracapsular extraction is disclosed. The intraocular lens includes an optical lens body, and a continuous ring-like member spaced from the rear surface of the lens body by a plurality of supporting bosses which are attached to and extend directly rewardly from a peripheral portion of the rear surface of the lens body. The continuous ring-like member is preferably made of PROLENE.RTM. and forms a resilient seal against the posterior capsule of the eye when implanted in the posterior capsule, thereby extending the period of time between cataract extraction and subsequent corrective micro-surgery necessitated by secondary cataract growth.

Abstract: A gas generator is provided which can be selectively switched between reaon and nonreaction modes. The gas generator incudes a reaction chamber which has top and bottom ends. The chamber contains reactive and nonreactive liquids, the nonreactive liquid having a greater specific gravity than the reactive liquid. A solid reactant member is provided. A device is provided for projecting the solid reactant member through the bottom of the chamber, thence through the nonreactive liquid, and thence into the reactive liquid for generating gas. Further, a device is provided for withdrawing the solid reactant member from the reactive liquid into the nonreactive liquid for terminating the generation of gas.