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Cc: Robert Dewar <dewar@adacore.com>,
   Gabriel Dos Reis <gdr@integrable-solutions.net>,
   gcc mailing list <gcc@gcc.gnu.org>
From: Andrew Pinski <pinskia@physics.uc.edu>
Subject: Re: signed is undefined and has been since 1992 (in GCC)
Date: Tue, 28 Jun 2005 13:52:00 -0000
To: Gabriel Paubert <paubert@iram.es>
X-SW-Source: 2005-06/txt/msg01111.txt.bz2


On Jun 28, 2005, at 9:46 AM, Gabriel Paubert wrote:

> Now in practice what would be the cost of checking that the divisor
> is -1 and take an alternate path that computes the correct
> results (in modulo arithmetic) for this case ?

Small compared the division it self but if it is in an inner loop, it
adds up and then becomes a performance regression which nobody wants.

-- Pinski