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Date: Wed, 31 Mar 2004 05:40:00 -0000
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From: "pinskia at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug optimization/14792] [tree-ssa] cast elimination opportunity involving an AND
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------- 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