[Bug rtl-optimization/27567] [4.0/4.1/4.2 Regression] __builtin_memcpy generates redundant stores/moves.

rguenth at gcc dot gnu dot org gcc-bugzilla@gcc.gnu.org
Fri May 12 08:27:00 GMT 2006



------- Comment #1 from rguenth at gcc dot gnu dot org  2006-05-12 08:27 -------
f is marked addressable and assigned a stack slot.  That the stores are not
optimized away later is probably due to aliasing issues - an open-coded memcpy
must behave like the -fno-strict-aliasing case, so I guess we applied measures
to assure this and this prevents this optimization.  3.3 and 3.3-hammer can do
the optimization.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |rguenth at gcc dot gnu dot
                   |                            |org, hubicka at gcc dot gnu
                   |                            |dot org
             Status|UNCONFIRMED                 |NEW
          Component|other                       |rtl-optimization
     Ever Confirmed|0                           |1
           Keywords|                            |missed-optimization
      Known to fail|                            |3.4.6 4.0.3 4.1.0 4.2.0
      Known to work|                            |3.3.6
   Last reconfirmed|0000-00-00 00:00:00         |2006-05-12 08:27:14
               date|                            |
            Summary|__builtin_memcpy generates  |[4.0/4.1/4.2 Regression]
                   |redundant stores/moves.     |__builtin_memcpy generates
                   |                            |redundant stores/moves.
   Target Milestone|---                         |4.0.4


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27567



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