Hi
I am having all sorts of problems with the TEST Call subcommand
specifically restoring the USER program R14 value
The Documentation says the return value whether you use RESUME "which
specifies upon completion of execution, the called program returns control
to the address of the last breakpoint before the CALL".
In this case r14 points to address of where the breakpoint is
Or you can explicitly set where you want to return by coding RETURN and
having R14 point to where you want to return
The problem is in either case one has to set the USER programs R14 back
What I wanted to do is return to the breakpoint which had the call only this
time without calling the user program
Now it seems to me the only way to get this done is by
First Save the address of where the breakpoint is upon entry
Then have R14 point to a DUMMY breakpoint by that I mean you have a workarea
obtained with TEST subcommand GETMAIN (passed as a parm) to the user prog
have some area 2 bytes with a nop
X'0700' and in the called program branch back to it so for example
use the following TEST subcommand
Assume the original R14 was saved in workarea+4
AT WORKAREA+30 (COPY WORKAREA+4 R14 LENGTH(4); AT WORKAREA+40? ; GO
WORKAREA+40?)
This code would
First seem to go to dummy breakpoint
Second retore the user program value of R14 Third set a breakpoint at the
original breakpoint (without a call) Fourth go to the breakpoint
However I keep on getting a S0C4
The following is snippets of the user program
USERPROG CSECT
USING R3,USERPROG
LR R3,R15
ST R14,RETURN
MVC DUMMYBREAK,=X'0700'
LA R14,DUMMYBREAK
BR R14
WORKAREA DSECT
0030 DUMMYBREAK DS XL2
0040 RETRUN DS A
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