Abstract: Various aspects provide for facilitating prediction of instruction pipeline hazards in a processor system. A system comprises a fetch component and an execution component. The fetch component is configured for storing a hazard prediction associated with a group of memory access instructions in a buffer associated with branch prediction. The execution component is configured for executing a memory access instruction associated with the group of memory access instructions as a function of the hazard prediction entry. In an aspect, the hazard prediction entry is configured for predicting whether the group of memory access instructions is associated with an instruction pipeline hazard.

Abstract: Various aspects provide for detecting ordering violations in a memory system. A system includes a prediction component and an execution component. The prediction component predicts whether a load instruction in the system is associated with an instruction pipeline hazard. The execution component allocates the load instruction to a queue buffer in the system in response to a prediction that the load instruction is not associated with the instruction pipeline hazard.

Abstract: Various aspects provide for facilitating prediction of instruction pipeline hazards in a processor system. A system comprises a fetch component and an execution component. The fetch component is configured for storing a hazard prediction associated with a group of memory access instructions in a buffer associated with branch prediction. The execution component is configured for executing a memory access instruction associated with the group of memory access instructions as a function of the hazard prediction entry. In an aspect, the hazard prediction entry is configured for predicting whether the group of memory access instructions is associated with an instruction pipeline hazard.

Abstract: Various aspects provide for detecting ordering violations in a memory system. A system includes a prediction component and an execution component. The prediction component predicts whether a load instruction in the system is associated with an instruction pipeline hazard. The execution component allocates the load instruction to a queue buffer in the system in response to a prediction that the load instruction is not associated with the instruction pipeline hazard.

Abstract: A method and system for maintaining memory coherence in a trace cache is disclosed. The method and system comprises monitoring a plurality of entries in a trace cache. The method and system includes selectively invalidating at least one trace cache entry based upon detection of a modification of the at least one trace cache entry. If modifications are detected, then corresponding trace cache entries are selectively invalidated (rather than invalidating the entire trace cache). Thus trace cache coherency is maintained with respect to memory in a performance and power-efficient manner. The monitoring further accounts for situations where more than one trace cache entry is dependent on a single cache line, such that modifications to the single cache line result in invalidations of a plurality of trace cache entries.

Abstract: Software hints embedded in branch instructions direct selection of one of a plurality of branch predictors to use when processing the branch instructions, leading to improved branch prediction (i.e. fewer mis-predictions) over conventional schemes. A software agent assembles branch instructions having associated respective branch predictor control fields compatible with a branch predictor selector and a plurality of branch predictors. Each branch predictor control field is used to perform branch predictor selection, branch predictor control, or both. Branch predictor selection enables selective branch prediction according to an appropriate one of the branch predictors as determined by the software agent by examining context surrounding the branch instruction. Branch predictor control enables control of operation of one or more of the branch predictors.

Abstract: A data communication system, such as a local area network, is provided with a capability of transmitting isochronous data. Preferably the system conveys both isochronous data and non-isochronous data by time-multiplexing the data into a recurring frame structure on a four-bit nibble basis. Switching of data is handled using switching tables. The tables can be updated by a processor. Updates can be performed asynchronously so that the processor does not have to wait until the switch tables are in an unused updatable state before outputting the update information. An efficient encoding scheme permits transmission of both isochronous and non-isochronous data over existing media, such as twisted pair, without degrading bandwidth previously achieved for non-isochronous data over the same media, such as using an Ethernet system. The arriving data is de-multiplexed at the hub into separate channels for handling the separate streams by appropriate hardware.

Abstract: A data communication system, such as a local area network, is provided with a capability of transmitting isochronous data. Preferably the system conveys both isochronous data and non-isochronous data by time-multiplexing the data into a recurring frame structure on a four-bit nibble basis. Switching of data is handled using switching tables. The tables can be updated by a processor. Updates can be performed asynchronously so that the processor does not have to wait until the switch tables are in an unused updatable state before outputting the update information. An efficient encoding scheme permits transmission of both isochronous and non-isochronous data over existing media, such as twisted pair, without degrading bandwidth previously achieved for non-isochronous data over the same media, such as using an Ethernet system. The arriving data is de-multiplexed at the hub into separate channels for handling the separate streams by appropriate hardware.