From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alan Modra <alan@spri.levels.unisa.edu.au>
To: ak@muc.de
Cc: egcs@cygnus.com
Subject: Re: Feature request: ability to describe x86 register halves as contraints.
Date: Tue, 30 Jun 1998 19:49:00 -0000
Message-id: <Pine.LNX.3.96.980701100534.29344A-100000@mullet.Levels.UniSA.Edu.Au>
References: <19980630135032.22058@kali.lrz-muenchen.de>
X-SW-Source: 1998-07/msg00009.html

On Tue, 30 Jun 1998 ak@muc.de wrote:

> > 	asm ("# %0 %b0 %h0 %w0 %k0" : : "q"(x));
> > 
> > yields
> > 
> > 	# %eax %al %ah %ax %eax
> 
> Ok, I feel stupid now, but to my defense I must say that this is not 
> documented in the info pages.

Yes, you have to dig into i386.md

Colin Plumb <colin@nyx.net> wrote a really good, tutorial style,
description of x86 constraints.  If you ask him, I guess he'd be happy to
send it to you.  His tutorial really ought to be part of egcs
documentation.