optimization/9279: [3.2 regression] [Sparc] combine bug

[Gabriel Dos_Reis]

The following reply was made to PR optimization/9279; it has been noted by GNATS.

From: Gabriel Dos_Reis <gdosreis@sophia.inria.fr>
To: "Christian Ehrhardt" <ehrhardt@mathematik.uni-ulm.de>
Cc: Matthias Klose <doko@cs.tu-berlin.de>,
   Eric Botcazou <ebotcazou@libertysurf.fr>, ebotcazou@gcc.gnu.org,
   frank@g-n-u.de, gcc-bugs@gcc.gnu.org, gcc-gnats@gcc.gnu.org
Subject: Re: optimization/9279: [3.2 regression] [Sparc] combine bug
Date: Wed, 29 Jan 2003 02:25:50 +0100 (MET)

 | > (2) possibly a wrong code generation -- David gave some
 | > references.
 | 
 | I must have missed this discussion, Could you give me a pointer?
 
 Sorry, that is part of e-mail exhancge I had with Eric Dadid
 yesterday.   Quoting him:
 
 	  This patch and the necessary PowerPC patch exposed other bugs in
   the compiler regarding REG_EQUAL notes in loop unrolling:
 
   2002-10-04  David Edelsohn  <edelsohn@gnu.org>
 
 	  * unroll.c (copy_loop_body): Remove REG_EQUAL note attached to
 	  copied instruction if the note is not loop invariant.
 
   The patches may have other co-dependencies we do not know about.
 
 Eric agreed with him.
 
 I would like to avoid last time minute patch chasing.
 
 -- Gaby