History Buffer for Multiple-Field Registers

摘要

An approach is provided in which a mapper control unit receives dispatch information corresponding to a dispatching instruction that targets some of the register fields in a register. The mapper control unit selects, in a history buffer, an available history buffer entry that includes multiple field sets, each including an itag field. In turn, the mapper control unit modifies some of the history buffer field sets, including the itag fields, based on the existing content stored in the targeted register fields.

主权项

1. A method implemented by an information handling system that includes a memory and a processor, the method comprising:
receiving dispatch information corresponding to an instruction, wherein the dispatch information identifies a subset of a plurality of register fields included in a register; selecting a history buffer entry included in a history buffer, wherein the history buffer entry comprises a plurality of history buffer field sets that each include an itag field, resulting in a plurality of itag fields included in the selected history buffer entry; and modifying a subset of the plurality of history buffer field sets using existing content from the identified subset of register fields, wherein the modifying includes storing one or more itag values in each of the itag fields included in each of the subset of history buffer field sets.