if icmpeq1 if icmpeq2 if icmpeq3 if_icmpeq4 if_icmpeq5 if_icmpeq6 MAR SP SP-1 MAR SP SP-1 OPC TOS TOS MDR Why do we need to temporarily copy TOS in OPC in cycle 4 and later use it for comparison in cycle 5 instead of doing the comparison in one cycle