[Bug tree-optimization/35229] New: Vectorizer doesn't support dependence created by predictive commoning

[irar at il dot ibm dot com]

The following type of dependence, similar to such that would be created by
predictive commoning (or even PRE), is not supported by the vectorizer: 

 for (i = 1; i <= i_2; ++i)
   {
     a[i] = (b[i] + x) * .5f;
     x = b[i];
   }


-- 
           Summary: Vectorizer doesn't  support dependence created by
                    predictive commoning
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: enhancement
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: irar at il dot ibm dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35229