[Bug tree-optimization/35518] [4.4 Regression] FAIL: gcc.c-torture/execute/20040709-1.c execution at -O2 and above

["pinskia at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #3 from pinskia at gcc dot gnu dot org  2008-03-31 06:30 -------
retmeN is being miscompiled by SRA, at least for powerpc-darwin with a changed
MOVE_RATIO.
retmeN (x)
{
  <unnamed-unsigned:29> x$i;
  <unnamed-unsigned:23> x$j;
  long long unsigned int SR.21;

<bb 2>:
  x$j = x.j;
  x$i = x.i;
  x.j = x$j;
  x.i = x$i;
  SR.21 = VIEW_CONVERT_EXPR<long long unsigned int>(x);
  <retval>.i = x$i;
  <retval>.j = x$j;
  <retval> = VIEW_CONVERT_EXPR<struct N>((long long unsigned int)
((<unnamed-unsigned:12>) (SR.21 >> 52) >> 4) << 52 | VIEW_CONVERT_EXPR<long
long unsigned int>(<retval>) & 4503599627370495);
  return <retval>;

}

This also produces way crappy code rather just doing a non bit-field copy.  I
don't know what SRA is trying to prove here.  The Move ratio value I changed
rs6000 to is 5 and this is definitely more than 5 words.


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
          Component|middle-end                  |tree-optimization
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2008-03-31 06:30:07
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35518