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Re: vector alignment question
- From: Richard Henderson <rth at redhat dot com>
- To: Steve Ellcey <sje at cup dot hp dot com>
- Cc: gcc at gcc dot gnu dot org
- Date: Wed, 8 Jun 2005 14:58:34 -0700
- Subject: Re: vector alignment question
- References: <200506081950.MAA29832@hpsje.cup.hp.com>
On Wed, Jun 08, 2005 at 12:50:32PM -0700, Steve Ellcey wrote:
> I noticed that vectors are always aligned based on their size, i.e. an
> 8 byte vector has an aligment of 8 bytes, 16 byte vectors an alignment
> of 16, a 256 byte vector an alignment of 256, etc.
>
> Is this really intended?
Yes.
> so it seems to be intentional, but it still seems odd to me, especially
> for very large vectors.
Hardware usually requires such alignment. Most folk don't use vectors
larger than some bit of hardware supports. One wouldn't want the ABI
to depend on whether that bit of hardware were actually present, IMO.
r~