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Re: [patch] tree-vrp.c: Avoid VR_ANTI_RANGE in a binary expression.

From: Diego Novillo <dnovillo at redhat dot com>
To: Andrew Pinski <pinskia at physics dot uc dot edu>
Cc: gcc-patches at gcc dot gnu dot org, Kazu Hirata <kazu at codesourcery dot com>
Date: Wed, 22 Jun 2005 11:49:43 -0400
Subject: Re: [patch] tree-vrp.c: Avoid VR_ANTI_RANGE in a binary expression.
References: <20050621.102542.74734287.kazu@codesourcery.com> <20050622152125.GA31004@topo.toronto.redhat.com> <0c2dd1f8a60fa0f629a5cc063393a14b@physics.uc.edu>

On Wed, Jun 22, 2005 at 11:30:09AM -0400, Andrew Pinski wrote:

> It is also MINUS_EXPR too.
>
It's the same handler.

> Wrong, this is also miscompiled as unsigned overflow is defined:
> unsigned int f(unsigned char a, unsigned  char b)
>
Ah, quite right.  Kazu, in that case, put the check in the
original place and add the condition along the lines of:

	if (flag_wrapv || UNSIGNED_TYPE_P (TREE_TYPE ...))


Diego.

References:
- [patch] tree-vrp.c: Avoid VR_ANTI_RANGE in a binary expression.
  - From: Kazu Hirata
- Re: [patch] tree-vrp.c: Avoid VR_ANTI_RANGE in a binary expression.
  - From: Diego Novillo
- Re: [patch] tree-vrp.c: Avoid VR_ANTI_RANGE in a binary expression.
  - From: Andrew Pinski

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