re PR tree-optimization/58277 (wrong code at -O3)

	PR tree-optimization/58277
	* tree-ssa-strlen.c (strlen_enter_block): If do_invalidate gave up
	after seeing too many stmts with vdef in between dombb and current
	bb, invalidate everything.

	* gcc.c-torture/execute/pr58277-1.c: New test.
	* gcc.c-torture/execute/pr58277-2.c: New test.

From-SVN: r202104

gcc/ChangeLog

+2013-08-30  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/58277
+	* tree-ssa-strlen.c (strlen_enter_block): If do_invalidate gave up
+	after seeing too many stmts with vdef in between dombb and current
+	bb, invalidate everything.
+
 2013-08-30  Richard Biener  <rguenther@suse.de>
 
 	* fold-const.c (fold_single_bit_test): Fix overflow test.

gcc/testsuite/ChangeLog

+2013-08-30  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/58277
+	* gcc.c-torture/execute/pr58277-1.c: New test.
+	* gcc.c-torture/execute/pr58277-2.c: New test.
+
 2013-08-30  Eric Botcazou  <ebotcazou@adacore.com>
 
 	* gcc.dg/guality/param-1.c: New test.

gcc/testsuite/gcc.c-torture/execute/pr58277-1.c

+/* PR tree-optimization/58277 */
+
+extern void abort (void);
+static int a[2];
+int b, c, d, *e, f, g, h, **i = &e, k, l = 1, n, o, p;
+static int **volatile j = &e;
+const int m;
+char u;
+
+int
+bar ()
+{
+  u = 0;
+  return m;
+}
+
+__attribute__((noinline, noclone)) void
+baz ()
+{
+  asm ("");
+}
+
+static int
+foo ()
+{
+  int t1;
+  g = bar ();
+  if (l)
+    ;
+  else
+    for (;; h++)
+      {
+	*i = 0;
+	o = *e = 0;
+	if (p)
+	  {
+	    f = 0;
+	    return 0;
+	  }
+	for (;; k++)
+	  {
+	    int *t2 = 0;
+	    int *const *t3[] = {
+	      0, 0, 0, 0, 0, 0, 0, 0, 0, &t2, 0, 0, &t2, &t2, &t2,
+	      &t2, &t2, 0, 0, 0, 0, 0, 0, 0, &t2, 0, 0, 0, 0, 0, 0,
+	      0, 0, 0, 0, &t2, 0, 0, 0, 0, 0, 0, 0, &t2, &t2,
+	      &t2, &t2, &t2, 0, 0, 0, 0, 0, 0, 0, &t2, 0, 0, 0,
+	      &t2, 0, 0, 0, &t2, 0, &t2, 0, 0, &t2, 0, 0, 0, 0,
+	      0, &t2, 0, 0, 0, 0, &t2, &t2, 0, 0, 0, 0, &t2, 0,
+	      0, 0, 0, 0, 0, 0, &t2, 0, 0, 0, 0, 0, &t2, 0, 0, 0,
+	      &t2, &t2
+	    };
+	    int *const **t4[] = {&t3[0]};
+	    **i = 0;
+	    if (**j)
+	      break;
+	    u = 0;
+	  }
+	*i = *j;
+	t1 = 0;
+	for (; t1 < 5; t1++)
+	  *i = *j;
+      }
+  *j = 0;
+  return 1;
+}
+
+int
+main ()
+{
+  int t5;
+  a[0] = 1;
+  {
+    int *t6[6] = {&d, &d};
+    for (n = 1; n; n--)
+      if (foo())
+	{
+	  int *t7[] = {0};
+	  d = 0;
+	  for (; u < 1; u++)
+	    *i = *j;
+	  *i = 0;
+	  *i = 0;
+	  int t8[5] = {0};
+	  *i = &t8[0];
+	  int *const *t9 = &t6[0];
+	  int *const **t10 = &t9;
+	  *t10 = &t7[0];
+	}
+  }
+  u = 0;
+  for (; b; b++)
+    for (t5 = 0; t5 < 10; t5++)
+      c = a[a[a[a[a[a[a[a[c]]]]]]]];
+
+  baz ();
+
+  if (!a[a[a[a[a[a[a[a[a[a[a[a[a[a[a[u]]]]]]]]]]]]]]])
+    abort ();
+
+  return 0;
+}

gcc/testsuite/gcc.c-torture/execute/pr58277-2.c

+/* PR tree-optimization/58277 */
+
+extern void abort (void);
+static int a[1], b, c, e, i, j, k, m, q[] = { 1, 1 }, t;
+int volatile d;
+int **r;
+static int ***volatile s = &r;
+int f, g, o, x;
+static int *volatile h = &f, *p;
+char n;
+
+static void
+fn1 ()
+{
+  b = a[a[a[a[a[a[a[a[b]]]]]]]];
+  b = a[a[a[a[a[a[a[a[b]]]]]]]];
+  b = a[a[b]];
+  b = a[a[a[a[a[a[a[a[b]]]]]]]];
+  b = a[a[a[a[a[a[a[a[b]]]]]]]];
+}
+
+static int
+fn2 ()
+{
+  n = 0;
+  for (; g; t++)
+    {
+      for (;; m++)
+	{
+	  d;
+	  int *u;
+	  int **v[] = {
+	    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	    0, 0, 0, 0, 0, &u, 0, 0, 0, 0, &u, &u, &u, &u, &u, &u, &u, 0,
+	    &u, 0, &u, &u, &u, 0, &u, &u, 0, &u, &u, &u, &u, 0, &u, &u, &u,
+	    &u, &u, 0, &u, &u, 0, &u, 0, &u, &u, 0, &u, &u, &u, &u, &u, 0,
+	    &u, 0, 0, 0, &u, &u, &u, 0, 0, &u, &u, &u, 0, &u, 0, &u, &u
+	  };
+	  int ***w[] = { &v[0] };
+	  if (*p)
+	    break;
+	  return 0;
+	}
+      *h = 0;
+    }
+  return 1;
+}
+
+static void
+fn3 ()
+{
+  int *y[] = { 0, 0, 0, 0, 0, 0, 0, 0 };
+  for (; i; i++)
+    x = 0;
+  if (fn2 ())
+    {
+      int *z[6] = { };
+      for (; n < 1; n++)
+	*h = 0;
+      int t1[7];
+      for (; c; c++)
+	o = t1[0];
+      for (; e; e--)
+	{
+	  int **t2 = &y[0];
+	  int ***t3 = &t2;
+	  *t3 = &z[0];
+	}
+    }
+  *s = 0;
+  for (n = 0;; n = 0)
+    {
+      int t4 = 0;
+      if (q[n])
+	break;
+      *r = &t4;
+    }
+}
+
+int
+main ()
+{
+  for (; j; j--)
+    a[0] = 0;
+  fn3 ();
+  for (; k; k++)
+    fn1 ();
+  fn1 ();
+ 
+  if (n)
+    abort ();
+
+  return 0;
+}

gcc/tree-ssa-strlen.c

@@ -1952,6 +1952,28 @@ strlen_enter_block (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED,
 		  int count_vdef = 100;
 		  do_invalidate (dombb, phi, visited, &count_vdef);
 		  BITMAP_FREE (visited);
+		  if (count_vdef == 0)
+		    {
+		      /* If there were too many vdefs in between immediate
+			 dominator and current bb, invalidate everything.
+			 If stridx_to_strinfo has been unshared, we need
+			 to free it, otherwise just set it to NULL.  */
+		      if (!strinfo_shared ())
+			{
+			  unsigned int i;
+			  strinfo si;
+
+			  for (i = 1;
+			       vec_safe_iterate (stridx_to_strinfo, i, &si);
+			       ++i)
+			    {
+			      free_strinfo (si);
+			      (*stridx_to_strinfo)[i] = NULL;
+			    }
+			}
+		      else
+			stridx_to_strinfo = NULL;
+		    }
 		  break;
 		}
 	    }