Abstract: A RISC processor having a data mover engine and instructions that associate register addresses with memory addresses. In an embodiment, the instructions include a read-tie instruction, a single write-tie instruction, a dual write-tie instruction, and an untie instruction. The read-tie, single write-tie, and dual write-tie instructions are used to associate software accessible register addresses with memory addresses. These associations effect the operation of the data mover engine such that, for the duration of the associations, the data mover engine routes data to and from associated memory addresses and the execution unit of the processor in response to instructions that specify moving data to and from the associated register addresses. The invention reduces the number of instructions and hardware overhead associated with implementing program loops in a RISC processor.

Abstract: A processor core and method for managing branch misprediction in an out-of-order processor pipeline. In one embodiment, the pipeline of the processor core includes a front-end instruction fetch portion, a back-end instruction execution portion, and pipeline control logic. Operation of the instruction fetch portion is decoupled from operation of the instruction execution portion. Following detection of a control transfer misprediction, operation of the instruction fetch portion is halted and instructions residing in the instruction fetch portion are invalidated. When the instruction associated with the misprediction reaches a selected pipeline stage, instructions residing: in the instruction execution portion of the pipeline are invalidated and the flow of instructions from the instruction fetch portion to the instruction execution portion of the processor pipeline is restarted.

Abstract: A processor core and method for managing program counter redirection in an out-of-order processor pipeline. In one embodiment, the pipeline of the processor core includes a front-end instruction fetch portion, a back-end instruction execution portion, and pipeline control logic. Operation of the instruction fetch portion is decoupled from operation of the instruction execution portion. Following detection of a control transfer misprediction, operation of the instruction fetch portion is halted and instructions residing in the instruction fetch portion are invalidated. When the instruction associated with the misprediction reaches a selected pipeline stage, instructions residing in the instruction execution portion of the pipeline are invalidated and the flow of instructions from the instruction fetch portion to the instruction execution portion of the processor pipeline is restarted.

Abstract: A method and a system for allocating memory in a memory buffer that is part of a data distribution device. Generally, the allocation of memory is for the purpose of storing datagrams. The method allocates memory in the buffer based, at least partially, on how ingress ports that are operably connected to the memory buffer have previously used the buffer to store datagrams. The system typically includes one or more detectors that monitor how various ingresses into the data distribution device are using and have used the memory buffer.

Abstract: Various methods are provided for distributing datagrams over telecommunications networks. According to many of these methods, datagrams are multicast or broadcast to one or more nodes or Virtual Local Area Networks (VLANs) on the networks. Also provided are systems for distributing datagrams over the networks according to these methods. According to some of these systems, reductions are provided in the amounts of memory used to multicast and/or broadcast datagrams.