[Bug tree-optimization/18317] New: Missed IV optimization (another one)

[steven at gcc dot gnu dot org]

This is another IV optimization we fail to catch. 
 
void 
strength_test6(int *data) 
{ 
  int j = data[0]; 
  int i = data[1]; 
  do { 
    data[data[2]] = 2; 
    i = i + j; 
  } while (i * 21 < data[3]); 
} 
 
void 
strength_result6(int *data) 
{ 
  int j = data[0] * 21; 
  int i = data[1] * 21; 
  do { 
    data[data[2]] = 2; 
    i = i + j; 
  } while (i < data[3]); 
}

-- 
           Summary: Missed IV optimization (another one)
           Product: gcc
           Version: 4.0.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: normal
          Priority: P2
         Component: tree-optimization
        AssignedTo: rakdver at gcc dot gnu dot org
        ReportedBy: steven at gcc dot gnu dot org
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18317