Apple Inc.
Zero cycle move using free list counts

Abstract:

A system and method for reducing the latency of data move operations. A register rename unit within a processor determines whether a decoded move instruction qualifies for a zero cycle move operation. If so, control logic assigns a physical register identifier associated with a source operand of the move instruction to the destination operand of the move instruction. Additionally, the register rename unit marks the given move instruction to prevent it from proceeding in the processor pipeline. Further maintenance of the particular physical register identifier may be done by the register rename unit during commit of the given move instruction.