Well, in reality you are right of course (who cares about the i-cache?) but
in theory one is branching around and NOT crashing, so not wasting the
i-cache is a desirable goal.
Charles
-Original Message-
From: IBM Mainframe Assembler List [mailto:ASSEMBLER-LIST@LISTSERV.UGA.EDU]
On Behalf Of Tony Thigpen
Sent: Saturday, May 13, 2017 7:20 PM
To: ASSEMBLER-LIST@LISTSERV.UGA.EDU
Subject: Re: Quick error termination of an assembler routine (Was:
Performance of Decimal Floating Point Instruction)
Who cares about the Instruction Cache? You are crashing the program.
Especially with just a one byte error code. We are talking about "it should
never get there" code, or test code to abend.
Tony Thigpen
Keven Hall wrote on 05/12/2017 06:53 PM:
> Regarding code like:
>> BZNOERROR (If RC==0.)
>> DCX'00',C'You shouldn'ta done that.'
>
> I'd suggest documenting the error in source code rather than the
instruction cache (or using a 1-byte numeric error code.
>
> Possibly I'm being pedantic. For sure I'm dragging this thread ever
further from its original subject.
>
> Keven
>
>> On May 12, 2017, at 11:57, Paul Gilmartin
<0014e0e4a59b-dmarc-requ...@listserv.uga.edu> wrote:
>>
>>> On 2017-05-12, at 09:56, somitcw wrote:
>>>
>>> My favourite was to branch to an odd address.
>>>
>>> S0C1 and S0C7 ABENDs are common, but any S0C6 abend was mine.
>>> If an operator called at 2:00AM, I would know who caused 3 pair of
socks.
>>>
>> Unfortunately, IIRC the exception occurs after the branch is taken so
>> the PSW provides no ready indication of the point of error.
>>
>>> Coding so that the assembler didn't flag it was needed but easy.
>>> Something like:
>>>
>>> BNE ERRLABEL-CSECT-1(BASEREG)
>>>
>> I suppose that could be doctored so the PSW points near either the
>> point at which the error was detected or to an error message.
>>
>> I think of:
>> BZNOERROR (If RC==0.)
>> DCX'00',C'You shouldn'ta done that.'
>> NOERROR DS0X
>>
>> -- gil
>
>
