EFFICIENTLY MANAGING SPECULATIVE FINISH TRACKING AND ERROR HANDLING FOR LOAD INSTRUCTIONS

摘要

Within a processor, speculative finishes of load instructions only are tracked in a speculative finish table by maintaining an oldest load instruction of a thread in the speculative finish table after data is loaded for the oldest load instruction, wherein a particular queue index tag assigned to the oldest load instruction by an execution unit points to a particular entry in the speculative finish table, wherein the oldest load instruction is waiting to be finished dependent upon an error check code result. Responsive to a flow unit receiving the particular queue index tag with an indicator that the error check code result for data retrieved for the oldest load instruction is good, finishing the oldest load instruction in the particular entry pointed to by the queue index tag and writing an instruction tag stored in the entry for the oldest load instruction out of the speculative finish table for completion.

主权项

1. A method, comprising:
tracking speculative finishes of load instructions only, from among a plurality of instructions executed in a processor, in a speculative finish table by maintaining an oldest load instruction of a thread in the speculative finish table after data is loaded for the oldest load instruction, wherein a particular queue index tag assigned to the oldest load instruction by an execution unit that executes the oldest load instruction from among a plurality of execution units points to a particular entry from among a plurality of entries in the speculative finish table, wherein the oldest load instruction is waiting to be finished dependent upon an error check code result; and responsive to receiving the particular queue index tag with an indicator that the error check code result for data retrieved for the oldest load instruction is good, finishing the oldest load instruction in the particular entry of the speculative finish table pointed to by the queue index tag and writing an instruction tag stored in the entry for the oldest load instruction out of the speculative finish table for completion.