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[Bug target/40170] redundant zero extensions



------- Comment #1 from rguenth at gcc dot gnu dot org  2009-05-17 19:47 -------
  byte >>= bit;

is according to C

  byte = (int)byte >> bit;

you see the (partly redundant) zero-extensions.  It has nothing to do with
partial register stalls.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|trivial                     |normal
  GCC build triplet|core2                       |
   GCC host triplet|linux                       |
           Keywords|                            |missed-optimization
            Summary|multiple movzx instructions |redundant zero extensions
                   |generated when no partial   |
                   |register stall is evident   |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40170


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