On 9/18/2022 4:15 PM, Tom Harper wrote:
Sometimes R15 contains the entry point.
If the routine receives control from ATTACHX or LINKX, for instance, and if it
is to run in AMODE(64), then it does not.
A better solution is to use
LARL R12,PROGNAME
USING PROGNAME, R12
which has no dependency on R15.
I prefer to use:
LARL R12,Constants
USING (Constants,Constants_End),R12
thereby dispensing with permanent base register coverage for program
executable code.
The address range between Constants and Constants_End contains the
literal pool and any other read-only constants the program might need.
This area is virtually always less than 4K in size, even for very large
programs.
--
Phoenix Software International
Edward E. Jaffe
831 Parkview Drive North
El Segundo, CA 90245
https://www.phoenixsoftware.com/
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