Multicore system for fusing instructions queued during a dynamically adjustable time window

Abstract

A technique to enable efficient instruction fusion within a computer system is disclosed. In one embodiment, a processor includes multiple cores, each including a first-level cache, a fetch circuit to fetch instructions, an instruction buffer (IBUF) to store instructions, a decode circuit to decode instructions, an execution circuit to execute decoded instructions, and an instruction fusion circuit to fuse a first instruction and a second instruction to form a fused instruction to be processed by the execution circuit as a single instruction, the instruction fusion occurring when both the first and second instructions have been stored in the IBUF prior to issuance to the decode circuit, and wherein the first instruction was the last instruction to be stored in the IBUF prior to the second instruction being stored in the IBUF, such that the first and second instructions are stored adjacently in the IBUF.