Re: BC 3.0 and 386's

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#358

From: Dave Stampe-Psy+Eng
Date: Mon, 10 Aug 1992 21:48

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 Ross Ridge <ross@zooid.guild.org> writes:
>
>I've always understood that under MS-DOS you can't depend on any
>of the '386 registers being preserved.  Anytime I've seen the 32bit
>registers used (eax, edi, ...) it's always been protected inside
>"sti ... cli" instructions to in case some ISR mucks with them.

But those are the top bits of a 32-bit register, not a segment register!
And the loading with a null segment really cannot be anything but 
deliberate.  It takes about 15 lines of assembley, and switching in
and out of protected mode to reload a segment descriptor.  So I doubt
its accidental.


--------------------------------------------------------------------------
| My life is Hardware,                    |                              | 
| my destiny is Software,                 |         Dave Stampe          |
| my CPU is Wetware...                    |                              | 
| Anybody got a SDB I can borrow?         | dstamp@watserv1.uwaterloo.ca |
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Path: arc1-ca.pugleaf.net!sparky!uunet!utcsri!torn!watserv2.uwaterloo.ca!watserv1!dstamp

References: <1992Aug10.091447.12146@zooid.guild.org>

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Newsgroups: comp.os.msdos.programmer
Path: arc1-ca.pugleaf.net!sparky!uunet!utcsri!torn!watserv2.uwaterloo.ca!watserv1!dstamp
From: dstamp@watserv1.uwaterloo.ca (Dave Stampe-Psy+Eng)
Subject: Re: BC 3.0 and 386's
Message-ID: <BssF9H.L05@watserv1.uwaterloo.ca>
Organization: University of Waterloo
References: <1992Aug10.091447.12146@zooid.guild.org>
Date: Mon, 10 Aug 1992 21:48:53 GMT
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