Output Register Information

When control returns to the caller of the IXLRT macro, the general purpose registers (GPRs) contain:

Register: Contents
0: Reason code if GPR15 return code is nonzero
1: Used as a work register by the system
2-13: Unchanged
14: Used as a work register by the system
15: Return code

When control returns to the caller of the IXLRT macro, the access registers (ARs) contain:

Register: Contents
0-1: Used as a work register by the system
2-13: Unchanged
14-15: Used as a work register by the system

For registers that the system changes, a caller who depends on these registers containing the same value before and after issuing the macro must save these registers before issuing the macro and restore them after the system returns control.