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Re: [PATCH] Fix PR target/28946

From: Rask Ingemann Lambertsen <rask at sygehus dot dk>
To: Roger Sayle <roger at eyesopen dot com>
Cc: Uros Bizjak <ubizjak at gmail dot com>, gcc-patches at gcc dot gnu dot org
Date: Tue, 5 Sep 2006 18:06:59 +0200
Subject: Re: [PATCH] Fix PR target/28946
References: <5787cf470609050406q1846f74dk312431cafe456bf5@mail.gmail.com> <Pine.LNX.4.44.0609050705430.23144-100000@www.eyesopen.com>

On Tue, Sep 05, 2006 at 07:20:02AM -0600, Roger Sayle wrote:

> Taking a small step backwards perhaps we're missing a completely
> different optimization here...  if (((unsigned)x >> 5) != 0) could
> probably be better expanded/transformed as if ((unsigned) x >= 32),
> especially on pentium-4s where the cost of a shift is significant.

   Additionally, it would need no scratch registers on some targets (such
as i386).

-- 
Rask Ingemann Lambertsen

References:
- [PATCH] Fix PR target/28946
  - From: Uros Bizjak
- Re: [PATCH] Fix PR target/28946
  - From: Roger Sayle

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