[Bug middle-end/28545] [4.1 Regression] Wrong code for hoisted multiplication

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

------- Comment #9 from rguenth at gcc dot gnu dot org  2006-10-14 10:40 -------
Much simpler testcase:

void foo(int);
void solver(int cr)
{
  int x, y, n;

  for (y = 0; y < cr; y++)
    for (x = 0; x < cr; x++) {
      for (n = 0; n < cr; n++)
        ;
      foo(cr*cr);
    }
}

t35.copyprop1:

;; Function solver (solver)

solver (cr)
{
  int n;
  int y;
  int x;
  int D.1293;

<bb 0>:
  goto <bb 6> (<L7>);

<L2>:;
  n_11 = n_3 + 1;

  # n_3 = PHI <0(4), n_11(1)>;
<L3>:;
  if (n_3 < cr_5) goto <L2>; else goto <L4>;

<L4>:;
  D.1293_9 = cr_5 * cr_5;
  foo (D.1293_9);
  x_10 = x_1 + 1;

  # x_1 = PHI <0(6), x_10(3)>;
<L5>:;
  if (x_1 < cr_5) goto <L3>; else goto <L6>;

<L6>:;
  y_7 = y_2 + 1;

  # y_2 = PHI <0(0), y_7(5)>;
<L7>:;
  if (y_2 < cr_5) goto <L5>; else goto <L8>;

<L8>:;
  return;

}

t36.vrp1:

solver (cr)
{
  int n;
  int y;
  int x;
  int D.1293;

<bb 0>:
  goto <bb 6> (<L7>);

<L2>:;
  n_11 = n_3 + 1;

  # n_3 = PHI <0(4), n_11(1)>;
<L3>:;
  if (n_3 < cr_5) goto <L2>; else goto <L4>;

<L4>:;
  D.1293_9 = cr_5 * cr_13;
  foo (D.1293_9);
  x_10 = x_1 + 1;

  # x_1 = PHI <0(6), x_10(3)>;
<L5>:;
  if (x_1 < cr_5) goto <L3>; else goto <L6>;

<L6>:;
  y_7 = y_2 + 1;

  # y_2 = PHI <0(0), y_7(5)>;
<L7>:;
  if (y_2 < cr_5) goto <L5>; else goto <L8>;

<L8>:;
  return;

}


(this smells like a tree sharing issue).


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28545