Method and system for efficiently utilizing rename buffers to reduce dispatch unit stalls in a superscalar processor

摘要

A method for reducing dispatch stalls includes tracking allocation and deallocation of real rename buffers for instructions dispatched by a dispatch unit, and providing at least one virtual rename buffer for allocation of an instruction when the real rename buffers have been allocated. The method further includes tagging the instruction allocated to the at least one virtual rename buffer with a rename buffer busy signal, wherein the rename buffer busy signal indicates to an execution unit that the instruction cannot be completed. An efficient system for utilization of rename buffers in a superscalar processor includes a plurality of rename buffers, a dispatch unit coupled to the plurality of rename buffers, and an allocation/deallocation table coupled to the dispatch unit and the plurality of rename buffers. Further, the table includes a plurality of real rename buffer slots and at least one virtual rename buffer slot. Additionally, a rename busy signal is provided for an instruction allocated to the at least one virtual rename buffer slot.