Subject: Re: [boost] Accelerating algorithms with SIMD - Segmented iterators and alternatives
From: David Abrahams (dave_at_[hidden])
Date: 2010-10-16 15:20:21
At Sat, 16 Oct 2010 19:01:12 +0100,
Mathias Gaunard wrote:
> On 15/10/2010 04:48, David Abrahams wrote:
> > At Thu, 14 Oct 2010 20:00:15 +0100,
> > Mathias Gaunard wrote:
> >> On 13/10/10 18:50, David Abrahams wrote:
> >>> I think you mean
> >>> 1 2 | 3 4 5 6 | 7 8 9 10 | 11
> >> What is that nonsense supposed to be?
> > I fear this conversation is becoming uncivil.
> Sorry, I just couldn't make sense of what this is supposed to be,
> and used bad phrasing.
> What would the value type of that range be?
> > That's what "if" statements are for.
> We want to avoid these.
Actually, you don't need them. This is really simple; it's just like
processing a deque.
> > Unless you process the uneven end bits with non-SIMD code.
> I would quite like a provide a way to do this.
> A range, however, must be homogeneous, and have all its elements be
> the same type, so it's either a scalar or a vector, can't be both.
That's where your problem is; you can't look at the "vectors" as
elements. They're just views used as an optimization technique for
operating on subsequences of a particular number of scalars.
-- Dave Abrahams BoostPro Computing http://www.boostpro.com
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