[Bug middle-end/35691] New: Missed (a == 0) && (b == 0) into (a|(typeof(a)(b)) == 0 when the types don't match

[pinskia at gcc dot gnu dot org]

While looking into PR 35429, I noticed this small missed optimization.
If we have:
typedef unsigned int1;

int foo(int z0, int1 z1)
{
  return z0 != 0 || z1 != 0;
}

int foo1(int z0, int1 z1)
{
  return z0 == 0 && z1 == 0;
}
--- CUT ---
Both of those should optimize as int is the same size as unsigned and we are
comparing against 0.  The same thing should happen with int and long on a ILP32
target.


-- 
           Summary: Missed (a == 0) && (b == 0) into (a|(typeof(a)(b)) == 0
                    when the types don't match
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: enhancement
          Priority: P3
         Component: middle-end
        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=35691