FUSING FLAG-PRODUCING AND FLAG-CONSUMING INSTRUCTIONS IN INSTRUCTION PROCESSING CIRCUITS, AND RELATED PROCESSOR SYSTEMS, METHODS, AND COMPUTER-READABLE MEDIA

摘要

Fusing flag-producing and flag-consuming instructions in instruction processing circuits and related processor systems, methods, and computer-readable media are disclosed. In one embodiment, a flag-producing instruction indicating a first operation generating a first flag result is detected in an instruction stream by an instruction processing circuit. The instruction processing circuit also detects a flag-consuming instruction in the instruction stream indicating a second operation consuming the first flag result as an input. The instruction processing circuit generates a fused instruction indicating the first operation generating the first flag result and indicating the second operation consuming the first flag result as the input. In this manner, as a non-limiting example, the fused instruction eliminates a potential for a read-after-write hazard between the flag-producing instruction and the flag-consuming instruction.