Inferring future value for speculative branch resolution in a microprocessor

Abstract

A system, processor, programming product and/or method including: an instruction dispatch unit configured to dispatch instructions of a compare immediate-conditional branch instruction sequence; and a compare register having at least one entry to hold information in a plurality of fields. Operations include: writing information from a first instruction of the compare immediate-conditional branch instruction sequence into one or more of the plurality of fields in an entry in the compare register; writing an immediate field and the ITAG of a compare immediate instruction into the entry in the compare register; writing, in response to dispatching a conditional branch instruction, an inferred compare result value into the entry in the compare register; comparing a computed compare result value to the inferred compare result value stored in the entry in the compare register; and not execute the compare immediate instruction or the conditional branch instruction.