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From: Ian Lance Taylor <>
Subject: Re: fixing i386 gas for 16-bit code
Date: Thu, 20 Jun 1996 08:46:00 -0000	[thread overview]
Message-ID: <> (raw)
In-Reply-To: <>

   Date: Wed, 19 Jun 1996 00:41:40 -0500
   From: VaX#n8 <>

   I was wondering if you know how hard it would be (for me) to fix gas
   to create 16-bit code properly, especially in the case of SIB (scaled
   indexed based) addressing modes on the i386.

I don't know much about the i386 myself, so I'm CC'ing your note to
the gas developers list,  Perhaps somebody on the
list will have some useful information.

   I have to hand code things like:

   movb 1(%si), %dh

   because it flubs the Mod-R/M byte.

   Another cool thing would be 8-bit offset addressing.  Coding all this by
   hand is hair-pulling material.  It is so ugly I chose not to do it :)

I used to hand code stuff when I was a kid, but it's pretty horrifying
to think that anybody still has to do it.

I believe that there are some 16 bit i386 assemblers out there.

   Would I have to learn bfd?  It confused the heck outta me when I looked
   at the bfd source last time :-/

You shouldn't have to look at BFD for this sort of thing.


       reply	other threads:[~1996-06-20  8:46 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <>
1996-06-20  8:46 ` Ian Lance Taylor [this message]
1996-06-20 11:02   ` erich
1996-06-20 11:07   ` erich
1996-06-20 11:28   ` Bryan Ford
1996-06-20 12:16     ` Ian Lance Taylor

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