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From: kds@intelca.UUCP (Ken Shoemaker)
Newsgroups: net.arch,net.lang,net.micro,net.micro.pc
Subject: Re: Re: Integer division on the Intel iAPX8[6,8]
Message-ID: <36@intelca.UUCP>
Date: Tue, 13-Aug-85 05:52:46 EDT
Article-I.D.: intelca.36
Posted: Tue Aug 13 05:52:46 1985
Date-Received: Sun, 18-Aug-85 23:01:12 EDT
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Organization: Intel, Santa Clara, Ca.
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Xref: linus net.arch:1488 net.lang:1483 net.micro:10239 net.micro.pc:4688

> Dividing the largest negative number by 1 works fine on the 68010 (16
> bit signed divide) and 68020 (32 bit signed divide); I tested it.  Has
> anybody tried an 80186 or 80286 yet?  They may have "fixed it in the
> next release".
> 
> PS:  Followups should go to net.arch only.

**sigh** I replied directly to the poster.  Yes, the 186 and the 286
add the most negative/signed two's complement number to the
acceptable results for division w/o a divide-by-zero trap.  It's
been fixed on every release (i.e., it was designed that way from
the start).  But not only that, extra hardware was added such that
multiples and divides take 1/4 the number of clocks.  So there...
-- 
...and I'm sure it wouldn't interest anybody outside of a small circle
of friends...

Ken Shoemaker, Microprocessor Design for a large, Silicon Valley firm

{pur-ee,hplabs,amd,scgvaxd,dual,qantel}!intelca!kds
	
---the above views are personal.  They may not represent those of the
	employer of its submitter.