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From: "pinskia at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug optimization/14792] [tree-ssa] cast elimination opportunity involving an AND
Date: Wed, 31 Mar 2004 05:40:00 -0000	[thread overview]
Message-ID: <20040331054024.1127.qmail@sources.redhat.com> (raw)
In-Reply-To: <20040331025513.14792.kazu@cs.umass.edu>


------- Additional Comments From pinskia at gcc dot gnu dot org  2004-03-31 05:40 -------
On PPC here is why this code is not optimial:
_foo:
        lbz r4,0(r3)
        extsb r0,r4   <--- extra extends byte
        rlwinm r2,r0,0,31,31  <-- as this is just an and 1 (trust me)
        cmpwi cr7,r2,0
        beqlr- cr7
        bnelr- cr7
        b _link_error

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14792


  parent reply	other threads:[~2004-03-31  5:40 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-03-31  2:55 [Bug optimization/14792] New: " kazu at cs dot umass dot edu
2004-03-31  3:34 ` [Bug optimization/14792] " pinskia at gcc dot gnu dot org
2004-03-31  5:40 ` pinskia at gcc dot gnu dot org [this message]
2004-03-31  5:43 ` pinskia at gcc dot gnu dot org
2004-05-24 18:13 ` [Bug tree-optimization/14792] " pinskia at gcc dot gnu dot org
2004-05-25 14:32 ` pinskia at gcc dot gnu dot org
2004-06-01 21:01 ` pinskia at gcc dot gnu dot org
2004-08-31  4:11 ` pinskia at gcc dot gnu dot org

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