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From: Falk Hueffner <falk.hueffner@student.uni-tuebingen.de>
To: "Kaspar Thommen" <kaspar@gmx.ch>
Cc: gcc-help@gcc.gnu.org
Subject: Re: g++ V3.3.1 not faster with __restrict
Date: Fri, 21 Nov 2003 10:42:00 -0000	[thread overview]
Message-ID: <87he0y0zqq.fsf@student.uni-tuebingen.de> (raw)
In-Reply-To: <24123.1069410397@www48.gmx.net>

"Kaspar Thommen" <kaspar@gmx.ch> writes:

> To my surprise, the __restrict version is not faster than the conventional
> one. In fact, they show the same speed. Do I have to specify any compilation
> option to tell g++ to really take advantage from the __restrict information?

No, although probably -O2 is required to show any difference.

> Didn't find anything in the docs however. I tried using -o, -o2,
> -o3, giving always equal speed for both functions.

Try -funroll-loops or -funroll-all-loops, this produces more
possibilities to take advantage of the non-aliasing.

-- 
	Falk

      reply	other threads:[~2003-11-21 10:42 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2003-11-21 10:26 Kaspar Thommen
2003-11-21 10:42 ` Falk Hueffner [this message]

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