The splitting of "store address" and "store data" is an intentional performance feature and not a "quirk" of the implementation. If you had a single store uop t

The splitting of "store address" and "store data" is an intentional performance feature and not a "quirk" of the implementation. If you had a single store uop then the memory system couldn't start doing a lookup on the address until the data to be stored was available. The data is usually the long pole. By having the address in a separate uop the data dependency is broken and the cache accesses allocating that line in the cache can be started much sooner.