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Re: Altivec + 16 byte alignment

From: Gabriel Paubert <paubert at iram dot es>
To: Franz Sirl <Franz dot Sirl-kernel at lauterbach dot com>
Cc: Richard Henderson <rth at redhat dot com>, John David Anglin <dave at hiauly1 dot hia dot nrc dot ca>, gcc at gcc dot gnu dot org, gianni at scaramanga dot co dot uk
Date: Thu, 13 Feb 2003 00:43:10 +0100
Subject: Re: Altivec + 16 byte alignment
References: <200302111725.h1BHP0rt016722@hiauly1.hia.nrc.ca> <200302122207.54496@enzo.bigblue.local> <20030212214621.GE29744@redhat.com> <200302122326.49019@enzo.bigblue.local>

On Wed, Feb 12, 2003 at 11:26:48PM +0100, Franz Sirl wrote:
> On Wednesday 12 February 2003 22:46, Richard Henderson wrote:
> > On Wed, Feb 12, 2003 at 10:07:54PM +0100, Franz Sirl wrote:
> > > ... and the stack pointer is kept aligned (to 256 bits) by
> > > independent code as well
> >
> > Is this 256 bits ABI mandated?  I.e. will a non-gcc ppc
> > compiler maintain this alignment as well?
> 
> Yep, ABI mandated, 256 bits for SYSV, 128 bits for EABI.

I believe that they are actually half of this, at least on 32 bit
targets. Alignment constraints of 128 and 64 appear quite frequently 
in the config/rs6000 files.

	Regards,
	Gabriel

References:
- Re: Altivec + 16 byte alignment
  - From: John David Anglin
- Re: Altivec + 16 byte alignment
  - From: Franz Sirl
- Re: Altivec + 16 byte alignment
  - From: Richard Henderson
- Re: Altivec + 16 byte alignment
  - From: Franz Sirl

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