[Bug tree-optimization/38497] New: PRE missing a load PRE which causes a loop to have two BBs

[pinskia at gcc dot gnu dot org]

Testcase:
void DoHuffIteration(int);
int f(int *a)
{
  int i;
  int plaintextlen=*a;
  for(i = 0; i< 10000; i++)
     DoHuffIteration(*a);
return *a - plaintextlen;
}

--- CUT ---
There is a load of *a after that loop even though we could have placed the load
inside the loop after the call.


-- 
           Summary: PRE missing a load PRE which causes a loop to have two
                    BBs
           Product: gcc
           Version: 4.2.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: enhancement
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: pinskia at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38497