Subject: Re: ARM ELF TODO list
To: Matt Thomas <matt@3am-software.com>
From: Ben Harris <bjh21@netbsd.org>
List: port-arm
Date: 04/27/2001 11:00:50
On Tue, 24 Apr 2001, Ben Harris wrote:

> On Tue, 24 Apr 2001, Matt Thomas wrote:
>
> > >* (gcc) Ensure 8-byte stack alignment on function entry
> >
> > Why 8 byte?
>
> I was onder the impression that ATPCS required this, but I can't find the
> reference now.

I think I've worked out what's going on.  The copy of ATPCS I've got at
home (and presumably the version Richard was referring to) is version B-01
(SWS ESPC 0002 B-01) and claims in section 3.1.1 ("The stack"):

# When a publicly visible function is called, the stack pointer value is
# 8-byte aligned.

The version currently offered by ARM's Web site by default is version
A-05 (SWS ESPC 0002 A-05), which doesn't contain that sentence.

-- 
Ben Harris                                                   <bjh21@netbsd.org>
Portmaster, NetBSD/arm26               <URL:http://www.netbsd.org/Ports/arm26/>