Date: Wed, 5 Jan 2000 08:40:25 +0500 (MVT)
From: Prashant TR <prashant_tr AT yahoo DOT com>
To: Nate Eldredge <neldredge AT hmc DOT edu>
cc: Martin Str|mberg <ams AT ludd DOT luth DOT se>, djgpp AT delorie DOT com
Subject: Re: Assembler instructions
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On Tue, 4 Jan 2000, Nate Eldredge wrote:

> > Is there an index over the instructions gas accept and what they do?
> > Right now it's what pusha/popa do that I'm interested in. Do they
> > push/pop all integer registers?
> 
> Your best bet is probably to head to www.intel.com and get a processor
> manual (big PDFs).  Then translate to AT&T syntax.
> 
> As for pusha, yes, that's approximately what it does.  I can't give
> you details (my usual references are currently 800 km away :) but
> Intel's manuals will have them in all their gore.

PUSHA pushes all the general purpose registers - ax, cx, dx, bx, sp,  bp,
si, di in that order. POPA does the reverse. PUSHAD/POPAD are for the
32-bit registers. But beware, don't depend on this order if you're writing
so commercial software. The infamous popad bug on some old 386s can
crash your system.

Prashant
---------------------------------------------------
One pound of learning requires ten pounds of common
sense to apply it.