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: >> BZ NOERROR (If RC==0.) >> DC X'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 <00000014e0e4a59b-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: >> BZ NOERROR (If RC==0.) >> DC X'00',C'You shouldn'ta done that.' >> NOERROR DS 0X >> >> -- gil > >
