[Bug rtl-optimization/55177] missed optimizations with __builtin_bswap

[ebotcazou at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55177

Eric Botcazou <ebotcazou at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2012-11-02
                 CC|                            |ebotcazou at gcc dot
                   |                            |gnu.org
          Component|tree-optimization           |rtl-optimization
            Summary|Missed optimisation: bswap, |missed optimizations with
                   |mask with constant, bswap   |__builtin_bswap
                   |back again.                 |
     Ever Confirmed|0                           |1
           Severity|normal                      |enhancement

--- Comment #2 from Eric Botcazou <ebotcazou at gcc dot gnu.org> 2012-11-02 10:56:17 UTC ---
If you don't need to swap, then do not use __builtin_bswap!  The first example
is really dumb.  That being said, the second example has some merit and we
should do something to optimize it at the RTL level.