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Re: Float point issue

From: Robert Dewar <dewar at adacore dot com>
To: Zoltán Kócsi <zoltan at bendor dot com dot au>
Cc: gcc at gcc dot gnu dot org
Date: Fri, 28 Oct 2011 07:28:38 -0400
Subject: Re: Float point issue
References: <20111028131705.62a2efa6@tade.bendor.com.au> <4EAA2202.6060808@adacore.com> <20111028153503.3df84e2f@tade.bendor.com.au>

On 10/28/2011 12:35 AM, Zoltán Kócsi wrote:

On Thu, 27 Oct 2011 23:31:14 -0400
Robert Dewar<dewar@adacore.com>  wrote:

- I am missing a gcc flag


probably you should avoid extra precision and all the
issues it brings, as well as speed up your program, by
using SSE 64-bit arithmetic (using the appropriate gcc
flags)


Indeed. -mpc64 fixes the issue and proper 53-bit rounding is applied.
Thanks a lot.


If you are going to set 64-bit mode, you might as well specify
SSE artihmetic, it will be significantly faster for most applications.

Zoltan

References:
- Float point issue
  - From: ZoltÃn KÃcsi
- Re: Float point issue
  - From: Robert Dewar
- Re: Float point issue
  - From: ZoltÃn KÃcsi

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