On 7/1/2016 10:33 PM, Paul Schuster wrote:
Ed:
Can you elaborate on the reason(s) for your methodology:
"We routinely load base registers and "uninitialized" pointers to
7FFFF000 (or sometimes 7FFFFBAD) rather than zero."
The one reason I can visualize is that instead of unintentionally
accessing something in low core you would experience a S0C4 instead.
That is the #1 reason! Of course, we now have the ZAD PER interrupt to
help catch accidental references to page zero that occur during in-house
testing, but that's not nearly as effective as a straight-up 0C4 abend!
The secondary reason is IEBEYEBALL of dumps, traces, etc. If an address
contains 7FFFFBAD then you know it's an intentionally "bad" address.
--
Edward E Jaffe
Phoenix Software International, Inc
831 Parkview Drive North
El Segundo, CA 90245
http://www.phoenixsoftware.com/
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