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* [Bug middle-end/35691]  New: Missed (a == 0) && (b == 0) into (a|(typeof(a)(b)) == 0 when the types don't match
@ 2008-03-25  4:32 pinskia at gcc dot gnu dot org
  2008-03-25  9:43 ` [Bug middle-end/35691] " rguenth at gcc dot gnu dot org
  0 siblings, 1 reply; 2+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2008-03-25  4:32 UTC (permalink / raw)
  To: gcc-bugs

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


^ permalink raw reply	[flat|nested] 2+ messages in thread
* [Bug middle-end/35691] Missed (a == 0) && (b == 0) into (a|(typeof(a)(b)) == 0 when the types don't match
  2008-03-25  4:32 [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
@ 2008-03-25  9:43 ` rguenth at gcc dot gnu dot org
  0 siblings, 0 replies; 2+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2008-03-25  9:43 UTC (permalink / raw)
  To: gcc-bugs



-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2008-03-25 09:42:22
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35691


^ permalink raw reply	[flat|nested] 2+ messages in thread
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2008-03-25  4:32 [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
2008-03-25  9:43 ` [Bug middle-end/35691] " rguenth at gcc dot gnu dot org

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