Registers on Entry

Register	Contents
1	address of the parameter list, INXPLIST, which is mapped by the IEHUEXIT macro
13	address of standard 72 byte save area
14	return address of the caller
15	entry point address of exit routine

Note: The 72 byte save area is provided solely in case the exit routine expects to be able to save the registers on entry. Its contents are not used by the Dynamic Exits Service Facility nor by IEHINITT.