Abstract: Various embodiments of microprocessors and methods of operating a microprocessor during runahead operation are disclosed herein. One example method of operating a microprocessor includes identifying a runahead-triggering event associated with a runahead-triggering instruction and, responsive to identification of the runahead-triggering event, entering runahead operation and inserting the runahead-triggering instruction along with one or more additional instructions in a queue. The example method also includes resuming non-runahead operation of the microprocessor in response to resolution of the runahead-triggering event and re-dispatching the runahead-triggering instruction along with the one or more additional instructions from the queue to the execution logic.

Abstract: Various embodiments of microprocessors and methods of operating a microprocessor during runahead operation are disclosed herein. One example method of operating a microprocessor includes identifying a runahead-triggering event associated with a runahead-triggering instruction and, responsive to identification of the runahead-triggering event, entering runahead operation and inserting the runahead-triggering instruction along with one or more additional instructions in a queue. The example method also includes resuming non-runahead operation of the microprocessor in response to resolution of the runahead-triggering event and re-dispatching the runahead-triggering instruction along with the one or more additional instructions from the queue to the execution logic.

Abstract: A digital signal processor which uses a RISC/CISC style front end and a VLIW style back end. Sequential ISA instructions are decoded into ?ops having a programmatic ordering. The ?ops are packed into a VLIW-like instruction packet according to a set of rules enforcing machine policy on e.g. data dependency, VLIW slot availability, maximum VLIW width, and so forth. Within the instruction packet, original program order is identified in case it is necessary to perform precise exception handling. The ISA code is executed as though it were on a RISC/CISC machine, but with VLIW style ILP efficiencies.

Abstract: Embodiments of the present invention relate to a memory management scheme and apparatus that enables efficient cache memory management. The method includes writing an entry to a store buffer at execute time; determining if the entry's address is in a first-level cache associated with the store buffer before retirement; and setting a status bit associated with the entry in said store buffer, if the address is in the cache in either exclusive or modified state. The method further includes immediately writing the entry to the first-level cache at or after retirement when the status bit is set; and de-allocating the entry from said store buffer at retirement. The method further may comprise resetting the status bit if the cacheline is allocated over or is evicted from the cache before the store buffer entry attempts to write to the cache.

Abstract: A context identifier is used in a cache memory apparatus. The context identifier may be written into the tag of a cache line or may be written as an addition to the tag of a cache line, during cache write operation. During a cache read operation, the context identifier of as issued instruction may be compared with the context identifier in the cache line's tag. The cache line's data block may be transferred if the context identifiers and the tags match.

Abstract: A method and apparatus for whacking a ?OP based upon the criticality of that ?OP. Also disclosed are embodiments of a method for determining the criticality of a ?OP.

Abstract: A method and device for determining an attribute associated with a locked load instruction and selecting a lock protocol based upon the attribute of the locked load instruction. Also disclosed is a method for concurrently executing the respective lock sequences associated with multiple threads of a processing device.

Abstract: A method and device for determining an attribute associated with a locked load instruction and selecting a lock protocol based upon the attribute of the locked load instruction. Also disclosed is a method for concurrently executing the respective lock sequences associated with multiple threads of a processing device.

Abstract: Embodiments of the present invention relate to a memory management scheme and apparatus that enables efficient cache memory management. The method includes writing an entry to a store buffer at execute time; determining if the entry's address is in a first-level cache associated with the store buffer before retirement; and setting a status bit associated with the entry in said store buffer, if the address is in the cache in either exclusive or modified state. The method further includes immediately writing the entry to the first-level cache at or after retirement when the status bit is set; and de-allocating the entry from said store buffer at retirement. The method further may comprise resetting the status bit if the cacheline is allocated over or is evicted from the cache before the store buffer entry attempts to write to the cache.

Abstract: A method and device for determining an attribute associated with a locked load instruction and selecting a lock protocol based upon the attribute of the locked load instruction. Also disclosed is a method for concurrently executing the respective lock sequences associated with multiple threads of a processing device.

Abstract: A context identifier is used in a cache memory apparatus. The context identifier may be written into the tag of a cache line or may be written as an addition to the tag of a cache line, during cache write operation. During a cache read operation, the context identifier of as issued instruction may be compared with the context identifier in the cache line's tag. The cache line's data block may be transferred if the context identifiers and the tags match.

Abstract: In an out-of-order execution computer system, a fast store forwarding buffer (FSFB) is conditionally signaled to output buffered store data of buffered memory store instructions to fill a buffered memory load instruction. The FSFB is coupled to a rotator so that the store data can be rotated from a first position to a second position. A control unit coupled with the FSFB determines whether or not to signal the FSFB to forward the store data. The control unit is also coupled with the rotator to signal the rotator whether and by how much to rotate the forwarded store data. The control unit is configured to detect a number of dependencies between a buffered memory load instruction and one or more buffered memory store instructions.

Abstract: A method and apparatus for whacking a &mgr;OP based upon the criticality of that &mgr;OP. Also disclosed are embodiments of a method for determining the criticality of a &mgr;OP.