[Bug middle-end/36326] New: gimplification of aggregate copies introduces extra aggregate copy

[rguenth at gcc dot gnu dot org]

union X { int i; double x; };

int foo (union X *p)
{
  union X x = *p;
  return x.x;
}

produces

  union X x.0;

  x.0 = *p;
  x = x.0;

this is not optimized at any point.  Using a struct instead usually SRA
is able to remove the extra copy.


-- 
           Summary: gimplification of aggregate copies introduces extra
                    aggregate copy
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: normal
          Priority: P3
         Component: middle-end
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: rguenth at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36326