Re: Word-1 of the Co nventional Save Area #8207;
On Thu, 4 Feb 2010 11:54:44 -0600, McKown, John wrote: Of course, I always zero 8(,13) just before I RETURN (in HLASM). Of course? Why? -- Tom Marchant -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Word-1 of the Co nventional Save Area #8207;
-Original Message- From: IBM Mainframe Discussion List [mailto:ibm-m...@bama.ua.edu] On Behalf Of Tom Marchant Sent: Thursday, February 04, 2010 12:54 PM To: IBM-MAIN@bama.ua.edu Subject: Re: Word-1 of the Co nventional Save Area On Thu, 4 Feb 2010 11:54:44 -0600, McKown, John wrote: Of course, I always zero 8(,13) just before I RETURN (in HLASM). Of course? Why? -- Tom Marchant Habit, I guess. I regard that as a dangling pointer which may or may not be valid, so I zero it. -- John McKown Systems Engineer IV IT Administrative Services Group HealthMarkets® 9151 Boulevard 26 • N. Richland Hills • TX 76010 (817) 255-3225 phone • (817)-961-6183 cell john.mck...@healthmarkets.com • www.HealthMarkets.com Confidentiality Notice: This e-mail message may contain confidential or proprietary information. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies of the original message. HealthMarkets® is the brand name for products underwritten and issued by the insurance subsidiaries of HealthMarkets, Inc. –The Chesapeake Life Insurance Company®, Mid-West National Life Insurance Company of TennesseeSM and The MEGA Life and Health Insurance Company.SM -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Word-1 of the Co nventional Save Area #8207;
Tom Marchant wrote: On Thu, 4 Feb 2010 11:54:44 -0600, McKown, John wrote: Of course, I always zero 8(,13) just before I RETURN (in HLASM). Of course? Why? So you know where the chain ends in a dump. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Word-1 of the Co nventional Save Area #8207;
On Thu, 4 Feb 2010 14:57:05 -0600, Rick Fochtman wrote: Tom Marchant wrote: On Thu, 4 Feb 2010 11:54:44 -0600, McKown, John wrote: Of course, I always zero 8(,13) just before I RETURN (in HLASM). Of course? Why? So you know where the chain ends in a dump. What's wrong with register 13? IAC, forward chain is not reliable. -- Tom Marchant -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Word-1 of the Co nventional Save Area #8207;
-Original Message- From: IBM Mainframe Discussion List [mailto:ibm-m...@bama.ua.edu] On Behalf Of Tom Marchant Sent: Thursday, February 04, 2010 3:43 PM To: IBM-MAIN@bama.ua.edu Subject: Re: Word-1 of the Co nventional Save Area On Thu, 4 Feb 2010 14:57:05 -0600, Rick Fochtman wrote: Tom Marchant wrote: On Thu, 4 Feb 2010 11:54:44 -0600, McKown, John wrote: Of course, I always zero 8(,13) just before I RETURN (in HLASM). Of course? Why? So you know where the chain ends in a dump. What's wrong with register 13? IAC, forward chain is not reliable. -- Tom Marchant What if R13 has been destroyed somehow? You can do forward chaining by starting at TCBFSA to the first save area, then using the pointer in word 3 of the save areas to chain forward until it is zero. That is what the SYSUDUMP formatter does. But I do agree that the forward chain is not always reliable. It is for every compiled language that I'm aware of. But it depends on the HLASM programmer following the convention if there is any assembler along the line. -- John McKown Systems Engineer IV IT Administrative Services Group HealthMarkets® 9151 Boulevard 26 • N. Richland Hills • TX 76010 (817) 255-3225 phone • (817)-961-6183 cell john.mck...@healthmarkets.com • www.HealthMarkets.com Confidentiality Notice: This e-mail message may contain confidential or proprietary information. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies of the original message. HealthMarkets® is the brand name for products underwritten and issued by the insurance subsidiaries of HealthMarkets, Inc. –The Chesapeake Life Insurance Company®, Mid-West National Life Insurance Company of TennesseeSM and The MEGA Life and Health Insurance Company.SM -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Word-1 of the Co nventional Save Area #8207;
No. Most compiled languages, including PL/1, don't do forward chaining. We did it by ourselves for years to make the SYSUDUMPs more readable. But in the end we gave up and wrote our own dump routine which follows the back chain starting from reg 13. In the LE manuals it is explicitly stated that LE does intentionally not do the forward chaining, although forward chaining has been an OS convention from the start, AFAIK. IMHO, the designers of LE violated the OS design principles for a long time, until - in the end - LE became part of the OS, and the OS conventions somehow got lost. Kind regards Bernd McKown, John schrieb: What if R13 has been destroyed somehow? You can do forward chaining by starting at TCBFSA to the first save area, then using the pointer in word 3 of the save areas to chain forward until it is zero. That is what the SYSUDUMP formatter does. But I do agree that the forward chain is not always reliable. It is for every compiled language that I'm aware of. But it depends on the HLASM programmer following the convention if there is any assembler along the line. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Word-1 of the Co nventional Save Area #8207;
A similar topic: entry points in SYSUDUMPs Save Area Trace can have a message attached, containing, for example, function names, compile dates etc., if the machine codes at the entry are coded in the right way. That is, Branch, one byte length field, the message. Our home grown start macro (and many others at other installations, as I'm sure) make use of this. But the compilers generate function prologues without these instructions, although it would be very easy (and helpful to the customers), if they would do otherwise. With some minor changes, the life of the software developers could be so much easier ... Sorry about that Bernd McKown, John schrieb: What if R13 has been destroyed somehow? You can do forward chaining by starting at TCBFSA to the first save area, then using the pointer in word 3 of the save areas to chain forward until it is zero. That is what the SYSUDUMP formatter does. But I do agree that the forward chain is not always reliable. It is for every compiled language that I'm aware of. But it depends on the HLASM programmer following the convention if there is any assembler along the line. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Word-1 of the Co nventional Save Area #8207;
2010/2/4 Bernd Oppolzer bernd.oppol...@t-online.de A similar topic: entry points in SYSUDUMPs Save Area Trace can have a message attached, containing, for example, function names, compile dates etc., if the machine codes at the entry are coded in the right way. That is, Branch, one byte length field, the message. Our home grown start macro (and many others at other installations, as I'm sure) make use of this. But the compilers generate function prologues without these instructions, although it would be very easy (and helpful to the customers), if they would do otherwise. With some minor changes, the life of the software developers could be so much easier ... Indeed. I once failed to convince a cow-orker that legible module prologues would be useful in his product: You just look at the load map, he said. Of course, that assumes you HAVE a load map that matches that version. He didn't understand how that could ever not be true... -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
