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Re: cc register usage on i386/2.96

To: Jan Hubicka <jh at suse dot cz>
Subject: Re: cc register usage on i386/2.96
From: Richard Henderson <rth at cygnus dot com>
Date: Tue, 29 Aug 2000 09:32:58 -0700
Cc: Andi Kleen <ak at suse dot de>, gcc-patches at gcc dot gnu dot org
References: <20000828015105.C1077@atrey.karlin.mff.cuni.cz> <20000828020055.A29832@gruyere.muc.suse.de> <20000828132826.A18570@atrey.karlin.mff.cuni.cz> <20000828144101.C28813@cygnus.com> <20000829115751.E1368@atrey.karlin.mff.cuni.cz>

On Tue, Aug 29, 2000 at 11:57:51AM +0200, Jan Hubicka wrote:
> Not always - you need to take care for overflows.
> Gcc does the converison for != 0, but not for > 0

Oh, ok.  Though we should really be doing it for the signed
comparisons, since overflow is undefined there.  But your 
patterns would still match for the unsigneds, so go ahead.

r~

Follow-Ups:
- Re: cc register usage on i386/2.96
  - From: Jan Hubicka
- Re: cc register usage on i386/2.96
  - From: Geoff Keating

References:
- Re: cc register usage on i386/2.96
  - From: Jan Hubicka
- Re: cc register usage on i386/2.96
  - From: Richard Henderson
- Re: cc register usage on i386/2.96
  - From: Jan Hubicka

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