[Bug tree-optimization/55869] different bit shift/or optimization.

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55869



Richard Biener <rguenth at gcc dot gnu.org> changed:



           What    |Removed                     |Added

----------------------------------------------------------------------------

           Keywords|                            |missed-optimization

             Status|UNCONFIRMED                 |NEW

   Last reconfirmed|                            |2013-01-04

     Ever Confirmed|0                           |1



--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> 2013-01-04 
10:36:52 UTC ---

In CCP we optimize this to



  <bb 2>:

  if (flag_2(D) != 0)

    goto <bb 4>;

  else

    goto <bb 3>;



  <bb 3>:



  <bb 4>:

  # iftmp.0_1 = PHI <144115188075855872(2), 0(3)>

  return iftmp.0_1;



before phiopt can apply valueization of flag ? 1 : 0.