Called assembler programs
A called assembler program must save the registers and store other information
in the save area passed to it by the COBOL program. In particular, the COBOL
save area must be properly back chained from the save area of an assembler
program. The assembler program must also contain a return routine that:
- Loads the address of the COBOL save area back into R13
- Restores the contents of the other registers
- Optionally sets a return code in R15
- Branches to the address in R14
- Returns to the COBOL caller in the same AMODE that was in use when it was called