| Re: [eigen] General questions about vectorization/alignment AGAIN |
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- To: eigen <eigen@xxxxxxxxxxxxxxxxxxx>
- Subject: Re: [eigen] General questions about vectorization/alignment AGAIN
- From: hauke strasdat <strasdat@xxxxxxxxx>
- Date: Tue, 18 Jan 2011 16:39:05 +0000
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Hi guys,
Thanks a lot for you comments! That really sharpened my understanding of the
alignment issue.
I think it would be a good idea to mention in the documentation that
it is safe to use
Eigen::aligned_alloctor as a replacement for std::allocator if its
convenient (e.g. for
templated code) and that it doesn't hurt either to use
EIGEN_MAKE_ALIGNED_OPERATOR_NEW exhaustively.
On Tue, Jan 18, 2011 at 3:02 PM, Benoit Jacob <jacob.benoit.1@xxxxxxxxx> wrote:
>> (Would be nice to add this info to
>> http://eigen.tuxfamily.org/dox-devel/TopicUnalignedArrayAssert.html.
>
> No interest in incitating users to write non-portable code.
I agree fully agree with you! However, I think it would be good to warn
the users in the documentation that their might be an alignment issues
even though their code did not trigger any assert on their specific
platform.
I developed my code under Linux x86-64. I was (almost) completely
ignorant about alignment issues until I tried the code under Linux x86-32.
It would be even better, if we could force asserts or warnings even
under systems
such as Linux x86-64. Is this any possible? Otherwise, I bet most
Linux x86-64 and
Win64 users won't be aware of, that their Eigen code might be non-portable.
Hauke S.