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References: <bug-37542-10053@http.gcc.gnu.org/bugzilla/>
Subject: [Bug tree-optimization/37542] [4.4 Regression] PRE doesn't simplify during phi-translation
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------- Comment #2 from rguenth at gcc dot gnu dot org  2008-09-16 15:34 -------
Hm, actually this is a regression :/  4.3 produces

foo (i, b)
{
  int prephitmp.7;
  int pretmp.6;
  int j;
  int D.1550;

<bb 2>:
  if (b_3(D) != 0)
    goto <bb 3>;
  else
    goto <bb 5>;

<bb 5>:
  pretmp.6_8 = 1 - i_4(D);
  goto <bb 4>;

<bb 3>:

<bb 4>:
  # prephitmp.7_9 = PHI <pretmp.6_8(5), 0(3)>
  # j_1 = PHI <1(5), i_4(D)(3)>
  D.1550_6 = prephitmp.7_9;
  return D.1550_6;

}


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to work|                            |4.3.2
            Summary|PRE doesn't simplify during |[4.4 Regression] PRE doesn't
                   |phi-translation             |simplify during phi-
                   |                            |translation
   Target Milestone|---                         |4.4.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37542