[Bug tree-optimization/30098] New: missed value numbering optimization

[dann at godzilla dot ics dot uci dot edu]

The following 2 functions should be compiled to the same thing. 
This is a test from Briggs' compiler benchmarks.

void vnum_test8(int *data)
{
  int i;
  int stop = data[3];
  int m = data[4];
  int n = m;
  for (i=0; i<stop; i++) {
    int k = data[2];
    data[k] = 2;
    data[0] = m - n;
    k = data[1];
    m = m + k;
    n = n + k;
  }
}
void vnum_result8(int *data)
{
  int i;
  int stop = data[3];
  for (i=0; i<stop; i++) {
    int k = data[2];
    data[k] = 2;
    data[0] = 0;
  }
}


-- 
           Summary: missed value numbering optimization
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: dann at godzilla dot ics dot uci dot edu
GCC target triplet: i686-pc-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30098