X'C4' trace entry

The X'CA' trace entry for Fast Path calls

 TRACE ID   = X'CA'
 
       word 0 — byte 1 - X'CA' - Exclusive control ENQ/DEQ (PI - 
                         Program Isolation) trace entry
                byte 2 - PST number (1)
                bytes 3-4 - Trace sequence number               
       word 1 — IRC1, indicating a Fast Path call                           
       word 2 - Call Function (GU, GN, and so on)
       word 3 - PROCOPT
       word 4 - PI time (also in reg 5 in Fast Path trace, 
                if active) 
       word 5 - A(PBC)
       word 6 - A(EPCB)
       word 7 - Not used