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[Bug tree-optimization/37541] VRP fails to optimize single-bit ranges



------- Comment #1 from rguenth at gcc dot gnu dot org  2010-07-28 14:43 -------
This seems fixed, just the optimizations in question are already performed
partly by FRE but one,

test2 (struct foo2 * x)
{
...
<bb 2>:
  D.2745_3 = BIT_FIELD_REF <*x_2(D), 8, 0>;
  D.2746_4 = D.2745_3 & 1;
  if (D.2746_4 == 0)
    goto <bb 5>;
  else
    goto <bb 3>;

<bb 3>:
  D.2750_6 = x_2(D)->i;


where for some reason our strange aggregate-bit-field-ref folding triggers
only for one load.


-- 

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         |2010-07-28 14:43:02
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37541


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