[Bug tree-optimization/16107] New: missed optimization with some math function builtins

["pinskia at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

Even after my tree combine pass, there are some math function builtins which I still not simplify 
because I do not regimplify calls expression yet.  I will handle this case after I sumbit and commit my 
tree-combiner.
double t(double x)
{
 x = -x;
 x = cos (x);
 return x;
}
double t1(double x)
{
 x = cos (-x);
 return x;
}

-- 
           Summary: missed optimization with some math function builtins
           Product: gcc
           Version: 3.5.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: enhancement
          Priority: P2
         Component: tree-optimization
        AssignedTo: pinskia at gcc dot gnu dot org
        ReportedBy: pinskia at gcc dot gnu dot org
                CC: gcc-bugs at gcc dot gnu dot org
 BugsThisDependsOn: 15459


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16107