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From: linden@fwi.uva.nl (Onno van der Linden)
Newsgroups: comp.sys.intel,comp.arch
Subject: Re: Intel bugs / bugged by Intel :-(
Message-ID: <1398@carol.fwi.uva.nl>
Date: 26 Oct 90 17:18:14 GMT
References: <JSP.90Oct25155458@glia.u.washington.edu>
Sender: news@fwi.uva.nl
Followup-To: comp.sys.intel
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jsp@glia.u.washington.edu (Jeff Prothero) writes:

[Stuff deleted]

>For the the record, the latest bug is that a POPAD followed by a MOV
>ECX, [EDX+EDI] will clobber EAX.  It appears that Intel got a little
>too aggressive on the pipelining here, and that the final POPAD cycle
>(which restores EAX) is being trashed by the address unit computations
>for [EDX+EDI].  Here's some code to reproduce the problem, provided
>courtesy of John Lauro (jal@acc.flint.umich.edu).  The bug has been
>detected on an old 16MHz '386 and a new 25MHz DX, and not on an SX.
>We haven't checked any other machines.

 Well, I checked the 386SX at home and it _does_ have the bug described
above.Are there any 'fixed' 386SX's on the market ?

[Program to detect bug deleted]

Onno van der Linden
linden@fwi.uva.nl