Backward compatibility due to algorithm alignment, feature disablement, or performance limitations

摘要

A new device that executes an application on a new CPU determines whether the application is for a legacy device having a legacy CPU. If the application is for a legacy device, the new CPU will disable selected features of the new CPU that do not exist on the legacy CPU, or the instruction execution latency of the new CPU will match or approximate the latency of the legacy CPU. Or change the algorithm details of the operation of one or more units of the new CPU to match or approximate the algorithm details of the operations of the corresponding unit of the legacy CPU and run the application. [Selection] Figure 2