From mboxrd@z Thu Jan  1 00:00:00 1970
From: hjl@nynexst.com (H.J. Lu)
To: dj@stealth.ctron.com (DJ Delorie)
Cc: gas2@cygnus.com, masaki@eie.minolta.co.jp, raeburn@cygnus.com (Ken Raeburn)
Subject: Re: [masaki@eie.monolta.co.jp: GAS bug and etc]
Date: Fri, 11 Nov 1994 06:45:00 -0000
Message-id: <9411111444.AA05506@titanic.nynexst.com>
References: <9411111438.AA11089@delorie>
X-SW-Source: 1994/msg00185.html

> 
> > Your patch jusr reversed what I did. Could you please tell
> > me why I was wrong and you were right? I thought I checked
> > the Intel x86 manual when I fixed that bug.
> 
> I didn't try to validate the patch; it was more of an FYI, which is
> why I included the header info.  If it's wrong, or you need more info,
> the original sender is the one to talk with (cc'd in both mails).
> Sorry if my intention wasn't clear.

I just hate that, especially when people say my patch is wrong without
doing their homework first :-).

> 
> Original sender:
> > From: masaki@eie.monolta.co.jp (Kenji  Masaki)
> 
> Note that the "jcxz" opcode in the gas that djgpp's libc was built
> with doesn't work as expected - jecxz does.  This might have confused
> people into thinking that there was a bug, or maybe there really is
> one.  jcxz is the 16-bit version (or pretends to be).
> 

jcxz and jecxz are totally different. One checks cx, the other
checks ecx. You have to decide what you want to use.

> Since jcxz uses both a register (opsize?) and an address (addrsize?),
> there may be a need for both prefixes.

I think gas will add a right address prefix automatically when it sees
a large offset. Ken?


-- 
H.J. Lu
NYNEX Science and Technology, Inc.			hjl@nynexst.com