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NNTP-Posting-Date: Sun, 08 Jan 2012 02:08:49 -0600
From: Gareth Owen <gwowen@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: The container abstraction and parallel programming
References: <je7uhf$hjj$1@speranza.aioe.org>
Date: Sun, 08 Jan 2012 08:08:49 +0000
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jacob navia <jacob@spamsink.net> writes:

> Today, more than 10 years tafter Intel introduced the first SIMD
> instructions it is still not possible to use those instructions to do
> SIMD programming when you use C and two mainstream compilers like gcc
> or MSVC.

Nonsense.  As well as the builtins already mentioned, GCC has
-ftree-vectorize which uses these SIMD instructions automatically when
the compiler can deduce that the aliasing rules allow it. Dot product
and matrix multiplication get a sizeable speed up when you use it.  
The 'restrict' keyword helps a lot, also