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Re: PRE (sometimes) confuses ivopts/scev?

From: Daniel Berlin <dberlin at dberlin dot org>
To: Ulrich Weigand <uweigand at de dot ibm dot com>
Cc: Richard Guenther <rguenth at tat dot physik dot uni-tuebingen dot de>, gcc at gcc dot gnu dot org
Date: Mon, 24 Jan 2005 19:17:29 -0500 (EST)
Subject: Re: PRE (sometimes) confuses ivopts/scev?
References: <200501242340.j0ONeXnn021133@53v30g15.boeblingen.de.ibm.com><Pine.LNX.4.60.0501241905540.27603@dberlin.org>

If you remove the test and replace it with 1, it'll never PRE anything.

IE the whole test :)

You surely can do better than the is_gimple_min_invariant test. Originally, i had it using SCEV + simple_iv, but this was a bit too expensive.

You might be able to get away with removing that part of the test, however.

References:
- Re: PRE (sometimes) confuses ivopts/scev?
  - From: Ulrich Weigand
- Re: PRE (sometimes) confuses ivopts/scev?
  - From: Daniel Berlin

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