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Re: [PATCH] Negation related constant folding improvements

From: Richard Henderson <rth at redhat dot com>
To: Roger Sayle <roger at eyesopen dot com>
Cc: gcc-patches at gcc dot gnu dot org
Date: Tue, 12 Aug 2003 21:38:57 -0700
Subject: Re: [PATCH] Negation related constant folding improvements
References: <20030811221213.GL24357@redhat.com> <Pine.LNX.4.44.0308121736370.24563-100000@www.eyesopen.com>

On Tue, Aug 12, 2003 at 06:24:54PM -0600, Roger Sayle wrote:
> It looks like the only place that we specially handle c4x's two's
> complement format is in encode_c4x_{single,double} where it looks
> as though we silently misencode the sign-dependent overflow.

Entirely likely, sadly.

> I'm quite happy to work to fix this (with help), but the hunk of my
> patch that you quote above can't change GCC's current behaviour.

I'm happy continuing to check TREE_OVERFLOW, even if this
bit is wrongly never set at present. 


r~

Follow-Ups:
- [PATCH] Negation related constant folding improvements (take 2)
  - From: Roger Sayle

References:
- Re: [PATCH] Negation related constant folding improvements
  - From: Richard Henderson
- Re: [PATCH] Negation related constant folding improvements
  - From: Roger Sayle

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