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Subject: Re: [OMPI users] is loop unrolling safe for MPI logic?
From: Jeff Squyres (jsquyres_at_[hidden])
Date: 2010-07-17 07:50:30


On Jul 17, 2010, at 4:22 AM, Anton Shterenlikht wrote:

> Is loop vectorisation/unrolling safe for MPI logic?
> I presume it is, but are there situations where
> loop vectorisation could e.g. violate the order
> of execution of MPI calls?

I *assume* that the intel compiler will not unroll loops that contain MPI function calls. That's obviously an assumption, but I would think that unless you put some pragmas in there that tell the compiler that it's safe to unroll, the compiler will be somewhat conservative about what it automatically unrolls.

-- 
Jeff Squyres
jsquyres_at_[hidden]
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