Here, the decrementing condition occurs when {HEAD ~ an issued non speculative store} is drained from the store buffer 552 via line 555 to {TAIL ~ main memory}, etc 
is drained to
Here , the decrementing condition occurs when { HEAD ~ an issued non speculative store } is drained from the store buffer 552 via line 555 to { TAIL ~ main memory } , etc
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL OTH OTH OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH