I found this command appears to show the asic # on a C3850XS-48. They are assigned in groups of 4 ports.
Switch#sh pl so fed sw 1 qos qsb interface tenGigabitEthernet 1/0/1QoS subblock information: Name:TenGigabitEthernet1/0/1 iif_id:0x00000000000...